U.S. patent application number 15/108274 was filed with the patent office on 2016-12-29 for use of 3d printing for anticounterfeiting.
This patent application is currently assigned to Verrana, LLC. The applicant listed for this patent is VERRANA, LLC. Invention is credited to Sharon Flank, William Flank, Rebecca Maksimovic, Edward R Poznysz, Gary Ritchie.
Application Number | 20160375676 15/108274 |
Document ID | / |
Family ID | 53682015 |
Filed Date | 2016-12-29 |
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United States Patent
Application |
20160375676 |
Kind Code |
A1 |
Ritchie; Gary ; et
al. |
December 29, 2016 |
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.
Inventors: |
Ritchie; Gary; (Thurmont,
MD) ; Maksimovic; Rebecca; (Washington, DC) ;
Flank; Sharon; (Washington, DC) ; Poznysz; Edward
R; (Needham Heights, MA) ; Flank; William;
(Chappaqua, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
VERRANA, LLC |
Silver Spring |
MD |
US |
|
|
Assignee: |
Verrana, LLC
Silver Spring
MD
|
Family ID: |
53682015 |
Appl. No.: |
15/108274 |
Filed: |
January 26, 2015 |
PCT Filed: |
January 26, 2015 |
PCT NO: |
PCT/US2015/012866 |
371 Date: |
June 24, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61931035 |
Jan 24, 2014 |
|
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|
Current U.S.
Class: |
428/29 |
Current CPC
Class: |
G01N 23/223 20130101;
B33Y 40/00 20141201; B29C 64/336 20170801; G01N 21/35 20130101;
B33Y 50/02 20141201; B33Y 70/00 20141201; G01N 21/33 20130101; B29K
2069/00 20130101; B29C 64/118 20170801; B33Y 10/00 20141201; B29K
2023/065 20130101; B29K 2105/16 20130101; G01N 21/65 20130101; B29K
2995/0035 20130101; B29K 2033/04 20130101; B29K 2067/003 20130101;
B29C 64/112 20170801; B29K 2509/00 20130101; B33Y 80/00 20141201;
G01N 21/6428 20130101; B33Y 30/00 20141201; B29K 2055/02 20130101;
B22F 3/008 20130101 |
International
Class: |
B33Y 10/00 20060101
B33Y010/00; B33Y 70/00 20060101 B33Y070/00; B33Y 30/00 20060101
B33Y030/00; B33Y 50/02 20060101 B33Y050/02; B29C 67/00 20060101
B29C067/00; B22F 3/00 20060101 B22F003/00 |
Claims
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)
Description
BACKGROUND
[0001] The present invention relates generally to the field of
identifying genuine product when created by 3D printing, through
the use of chemical taggants or additives, in quantities ranging
from fractional parts per million to 10% of the total sample, as
well as controlled media formulation variations. The chemical
taggants or formula variations act as a fingerprint, which can be
detected using a chemical analyzer, e.g., a spectrometer, in one or
more regions of the electromagnetic spectrum (including
ultraviolet, visible, near-infrared, mid-infrared, x-ray
fluorescence).
[0002] 3D printing is increasingly acknowledged as vulnerable to
counterfeiting.
(http://www.scientificamerican.com/article/3-d-printing-will-be-a-counter-
feiters-best-friend/). There are two basic paths to creating
counterfeits with 3D printing. An existing object (including a
genuine branded or licensed product) can be 3D-scanned to create
the instructions, or blueprint, for printing a copy. Alternatively,
the instructions, or blueprint, can be created as software, and
then shared. Hybrids of the two paths also exist, e.g., a 3D scan
version that is then altered to change one or more
characteristics.
[0003] Simply requiring that the blueprint file contain an
authorization code (Jung, et al., U.S. Pat. No. 8,286,236) is not
enough to prevent all types of 3D counterfeiting. The authorization
code validates the printing process, but leaves no trace of that
validation (or the lack of it) on the product that is generated.
Apple's application 20130341400 (Simon Larocque-Lancaster)
addresses a physical 3D mark, but again, this is minimal
protection, in this case because it assumes the ability to tuck
away a visible mark unobtrusively.
[0004] Using authorized material alone is also insufficient, in the
same way that it is possible to use genuine Hewlett Packard ink in
a genuine Hewlett Packard printer . . . to make illegal copies of a
copyrighted work, or to print a plagiarized document. Encoding the
instructions for materials tagging into the blueprint makes it
possible to use software controls (authorized secure downloads) to
limit proliferation of physical copies.
[0005] Limiting unauthorized versions is important to brand owners
and important for public safety. Brand owners want a way to ensure
that the products in the marketplace are genuine, both to ensure
quality and to ensure that they are getting paid for their work.
They see 3D printing as an opportunity and a threat. It constitutes
an opportunity to offer personalized, custom versions of a wide
range of products, from shoes to jewelry, spare parts to medical
implants. However, it also threatens their brand, their quality,
and their market: how can they distinguish a branded athletic shoe
from a knockoff, or a customized medical implant from a dangerous
chunk of plastic, if both are 3D printed? Brand owners currently
spend millions on ensuring that their products in the marketplace
are genuine, employing quality inspectors, secret shoppers,
security teams and forensic laboratories, many incorporating
spectroscopic and other chemical analysis tools. These teams check
distributors, monitor suspect products at customs in cooperation
with border authorities, and visit retailers to keep tabs on their
supply chain. When knockoffs slip through, the brand owners are
alerted when suspect product is returned, often because it failed,
and their labs spend time and money searching for the cause of
failure, or attempting to prove that the failed product is in fact
a fake. Authentication is the fastest-growing segment of the
broader anti-counterfeiting market, because faster--and more
portable--ways to check on products save money, time and
reputation.
[0006] The existing anti-counterfeiting effort is, however,
insufficient to meet the challenges of 3D printing, thus inspiring
the current invention.
[0007] Different 3D printing media have different curing methods,
but all are amenable to chemical fingerprinting.
[0008] Methods for 3D printing include:
[0009] fused deposition modeling (FDM), the technology that squirts
the melted plastic out the head of the 3D printer, on which a major
patent expired in 2009 (U.S. Pat. No. 5,121,329 A). The
heat-tolerance requirements for a taggant in this case are in the
range of 250 C, which somewhat restricts the universe of available
taggants, but still allows multiple cost-effective, safe
choices.
[0010] Selective Laser Sintering (SLS)--a high-quality 3D-printing
technology that can use metal, glass and ceramic materials as
media, cured by lasers, based on a now-expired series of patents
filed by Carl Deckard in the 1990s (U.S. Pat. No. 5,597,589 A)
[0011] Stereolithographic (or SLA) 3D Printing Techniques--which
put down a thin layer of resin that is cured with a UV laser (U.S.
Pat. No. 4,575,330 A), either cured, layer by layer, as each layer
is exposed to the UV curing as it moves up on a platform in a vat
of liquid photopolymer, or deposited (as in a spray) in layers.
[0012] Some methods melt or soften material to produce the layers,
e.g., selective laser melting (SLM), e.g. of aluminum mixtures, or
direct metal laser sintering (DMLS).
[0013] With laminated object manufacturing (LOM), thin layers are
cut to shape and joined together (e.g., paper, polymer, metal).
[0014] 3D printing here is to be understood to include all types of
sequential-layer material addition/joining throughout a 3D work
envelope under automated control. Related technologies, also to be
included, are desktop manufacturing, rapid manufacturing, and
on-demand manufacturing.
[0015] The term 3D printing originally referred to a process
employing standard and custom inkjet print heads. The most
prevalent 3D technology--especially hobbyist and consumer-oriented
models--is fused deposition modeling, a special application of
plastic extrusion.
[0016] Additive Manufacturing (AM) processes for metal sintering or
melting (such as selective laser sintering, direct metal laser
sintering, and selective laser melting) are included.
[0017] Applications for AM technologies that may need to identify
genuine product include architecture, construction, industrial
design, automotive, aerospace, military, engineering, dental and
medical industries, biotech (implantables and human tissue
replacement), fashion, footwear, jewelry, eyewear, food, and spare
parts.
[0018] 3D scanning is a process of analyzing and collecting digital
data on the shape and appearance of a real object. Based on this
data, three-dimensional models of the scanned object can then be
produced.
[0019] Models or blueprints are available on 3D printing
marketplaces on the Internet such as Shapeways, Thingiverse,
MyMiniFactory and Threeding.
SUMMARY
[0020] The current invention makes it possible to create a
specially-marked genuine or authorized version of an item, print it
with a 3D printer, then validate it in the field with a
spectrometer or similar chemical analysis device.
[0021] This represents a significant improvement over existing
methods because it is rapid, convenient, inexpensive, and aligns
well with the 3D design and printing process, while overcoming the
problem of rogue copying inherent in the rise of 3D printing.
Tagging can be covert, in particular because spectroscopic (rather
than visual) detection makes it possible for the taggant layer to
be below the surface of the finished 3D-printed object. This
under-the-skin tagging represents a substantial advance in
security.
[0022] To describe this in a different way, a manufacturing method
creates an object, using additive manufacturing for two materials
that look, to the human eye, to be the same color, but that differ
when tested with a spectrometer. In other words, an object is
manufactured and contains portions of two materials that look, to
the human eye, to be the same color, but that differ when tested
with a spectrometer.
[0023] The tagging in layers also represents a considerable advance
over simply mixing a taggant chemical into a single printing
medium, since it makes possible a much larger number of tag options
(e.g. in the top left corner, layered 1-2-3, or 1-3-2, or 2-3-1, or
2-double-thickness-3-1, or in the bottom right corner, and so
on).
[0024] To describe this in a different way, an object is created
using additive manufacturing, with one material creating an initial
shape, and a patch of a different, spectroscopically-detectable
material layered on so that it can be detected by a spectrometer,
and then covered with a third material so that the patch, though
covered, is still spectroscopically detectable. In other words, an
additive manufacturing method creates an object, with one material
creating an initial shape, and a patch of a different,
spectroscopically-detectable material is layered on so that it can
be detected by a spectrometer, and then covered with a third
material so that the patch, though covered, is still
spectroscopically detectable.
[0025] The field of the invention pertains to brand protection and
anti-counterfeiting. More specifically, 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 of
the product, and aesthetics. Even more specifically, the invention
pertains to the use of a spectral pattern employing 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.
[0026] The invention includes taggant or taggants, including those
that are mixed in or layered within or onto the printed object. The
invention also includes controlled variations in the formulation of
the multi-component media.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The invention is described with respect to a drawing in
several figures. Where possible, like elements among the figures
are denoted with like reference numerals.
[0028] FIG. 1 is a diagram illustrating an authorized 3D-printed
object containing one or more layers of taggant or differential
media, implemented in a sub-surface layer on a particular spot on
the product, and a visually similar unauthorized 3D-printed object
containing no taggant, according to an embodiment of the
disclosure.
[0029] FIG. 2 is a diagram illustrating a 3D-printer using
differential printing media to create a spectroscopically-tagged
authorized version of an object, according to an embodiment of the
disclosure.
[0030] FIG. 3 is a diagram of a 3D printer that portrays the result
of employing different chemicals to create a 3D object with taggant
source material or controlled media formulation variation,
according to an embodiment of the disclosure.
[0031] FIG. 4 is a diagram illustrating light scattering caused by
diffuse reflection on a 3D-printed object containing a sub-surface
layer consisting at least partly of open space, according to an
embodiment of the disclosure.
[0032] FIG. 5 is a conceptual chart illustrating the use of
software instructions to manage the layered
spectroscopically-detectable taggant used to create an authorized
3D-printed object, according to an embodiment of the
disclosure.
[0033] FIG. 6 is a conceptual chart illustrating delivery modes for
spectroscopically-detectable taggant, according to an embodiment of
the disclosure.
[0034] FIG. 7 is a conceptual chart illustrating secrecy management
for spectroscopically-detectable tagging of an authorized
3D-printed object, according to an embodiment of the
disclosure.
[0035] FIG. 8 is a conceptual chart illustrating mix, layering, and
color options for spectroscopically-detectable tagging of an
authorized 3D-printed object, according to an embodiment of the
disclosure.
[0036] FIG. 9 is a conceptual chart illustrating the use of
spectroscopically-detectable tagging for encoding of product data,
according to an embodiment of the disclosure.
[0037] FIG. 10 is a conceptual chart illustrating curing methods
for spectroscopically-detectable tagging of an authorized
3D-printed object, according to an embodiment of the
disclosure.
[0038] FIG. 11 is a conceptual chart illustrating structuring
methods for spectroscopically-detectable tagging of an authorized
3D-printed object, according to an embodiment of the
disclosure.
[0039] FIG. 12 is a conceptual chart illustrating an authentication
system for validating print media using a spectrometer integrated
into a 3D printer, according to an embodiment of the
disclosure.
[0040] FIG. 13 is a diagram illustrating an example of a system for
authorizing or prohibiting 3D scanning of non-authorized versions
of a 3D object, according to an embodiment of the disclosure.
[0041] FIG. 14 is a diagram illustrating a stereolithographic 3D
printer with an authentication system for validating print media
using a spectrometer integrated into the vat, according to an
embodiment of the disclosure.
[0042] FIG. 15 is a diagram illustrating authentication of a
3D-printed object using near-infrared (NIR) spectroscopy, according
to an embodiment of the disclosure.
[0043] FIG. 16 is a diagram consisting of a graph of the
near-infrared spectra of authentic and counterfeit 3D-printed
objects, according to an embodiment of the disclosure.
[0044] FIG. 17 is a diagram illustrating authentication of a
3D-printed object using ultraviolet and visible (UV/Vis)
spectroscopy, according to an embodiment of the disclosure.
[0045] FIG. 18 is a diagram consisting of a graph of the UV/Vis
spectra of authentic and counterfeit 3D-printed objects, according
to an embodiment of the disclosure.
[0046] FIG. 19 is a diagram illustrating authentication of a
3D-printed object using fluorescence spectroscopy, according to an
embodiment of the disclosure.
[0047] FIG. 20 is a diagram consisting of a graph of the
fluorescence spectra of authentic and counterfeit 3D-printed
objects, according to an embodiment of the disclosure.
[0048] FIG. 21 is a diagram illustrating authentication of a
3D-printed object using x-ray fluorescence spectroscopy (XRF),
according to an embodiment of the disclosure.
[0049] FIG. 22 is a diagram consisting of a graph of the x-ray
fluorescence spectra of authentic and counterfeit 3D-printed
objects, according to an embodiment of the disclosure.
[0050] FIG. 23 is a diagram illustrating authentication of a
3D-printed object using Raman spectroscopy, according to an
embodiment of the disclosure.
[0051] FIG. 24 is a diagram consisting of a graph of the Raman
spectra of authentic and counterfeit 3D-printed objects, according
to an embodiment of the disclosure.
[0052] FIG. 25 is a diagram illustrating the creation of a tagged
article of manufacture using a UV-cure resin 3D printer, according
to an embodiment of the disclosure.
[0053] FIG. 26 is a diagram illustrating the authentication, using
near-infrared spectroscopy, of a tagged article of manufacture
created using a UV-cure resin 3D printer, according to an
embodiment of the disclosure.
[0054] FIG. 27 is a diagram illustrating the authentication, using
UV/Vis spectroscopy, of a tagged article of manufacture created
using a hot-melt-plastic 3D printer, according to an embodiment of
the disclosure.
[0055] FIG. 28 is a diagram illustrating the authentication, using
fluorescence spectroscopy, of a tagged article of manufacture
created using a hot-melt-plastic 3D printer, according to an
embodiment of the disclosure.
[0056] FIG. 29 is a diagram illustrating the authentication, using
x-ray fluorescence spectroscopy, of a tagged article of manufacture
created using a 3D metal powder printer, according to an embodiment
of the disclosure.
[0057] FIG. 30 is a diagram illustrating the authentication, using
Raman spectroscopy, of a tagged article of manufacture created
using a hot-melt-plastic 3D printer, according to an embodiment of
the disclosure.
DETAILED DESCRIPTION OF THE DRAWINGS
[0058] FIG. 1 is a diagram illustrating an authorized 3D-printed
object 2 containing one or more layers of taggant 3 or differential
media, implemented in a sub-surface layer on a particular spot on
the product, and a visually similar unauthorized 3D-printed object
1 containing no taggant, according to an embodiment of the
disclosure.
[0059] To describe this in a different way, an object created by
additive manufacturing is composed of two materials that look the
same to the human eye, but shows different values when subjected to
a non-destructive analysis. The non-destructive analysis includes
spectroscopy.
[0060] FIG. 2 is a diagram illustrating an authorized 3D-printed
object 2 containing a sub-surface layer 4 of taggant or
differential media, and a surface layer 5 of a different material,
implemented on a particular spot on the product.
[0061] To describe this in a different way, an additive
manufacturing method is carried out so that the resulting object is
composed of materials that look the same to the human eye, but
different to a non-destructive analysis. The non-destructive
analysis includes spectroscopy, and the authenticity of the object
may be determined.
[0062] FIG. 3 is a diagram of a 3D printer 6 that portrays the
result of employing different chemicals to create a 3D object 2
with taggant source material 7 or controlled media formulation
variation. In this embodiment, one of the three media used to
create the 3D object is detectable by spectroscopic or similar
means (explained in detail in FIGS. 15 through 24), and it is mixed
in or layered in as the object is printed.
[0063] To describe this in a different way, a manufacturing method
creates an object, with one material having a first value when
subjected to non-destructive analysis such as spectroscopy, and a
second material with a different, second value when subjected to
non-destructive analysis, and then more of the first material,
making the second material invisible to the human eye. The second
material when subjected to non-destructive analysis indicates
information such as the authenticity of the object.
[0064] In other words, an object, created by additive
manufacturing, has one material having a first value when subjected
to non-destructive analysis such as spectroscopy, and a second
material with a different, second value when subjected to
non-destructive analysis, and then more of the first material,
making the second material invisible to the human eye.
[0065] In the simplest embodiment, a single taggant is applied as
an outer or near-final, non-surface ("under-the-skin") layer on the
near-finished object. Layers range from 16 to 100 microns in
current commercial printers, but it is easy to imagine that the
principle of tagging applies regardless of the exact thickness.
[0066] Other tagging options include: [0067] a. Applying a mix of
chemicals to create an outer layer of taggant [0068] b. Applying
chemicals to create a taggant that is applied on a part of the
object at the outer layer [0069] c. Applying chemicals to create a
taggant that is close to the outer layer (within the 1 mm-2 mm
depth path length for detection using near-infrared spectroscopy,
for example), but not the outer layer [0070] d. Using a mix of
chemicals and air chambers to create a taggant fingerprint that
leverages the ability of, for example, near-infrared spectroscopy
to take into account particle size and thickness [0071] e. Using an
authorized printing medium or mix of media to serve as a
fingerprint, for example in the case of a spare part that must be
of a certain strength and flexibility
[0072] FIG. 4 is a diagram illustrating light scattering caused by
diffuse reflection on a 3D-printed object containing a sub-surface
layer 7 consisting at least partly of open space. The layer 7 layer
containing empty spaces for channels, with supporting pillars is
created atop other layers 6 of an object in order to create, for
example, channels. Potential uses for space-containing layers
include biologic implants where internal structures or channels are
marked so flow can be monitored spectroscopically
[0073] Spectroscopic detection of the space-containing layer occurs
when incident light 8 bounces off the material and spaces, creating
both diffuse reflected light 9 and specular reflected light 10.
[0074] When light shines onto a sample with spaces, it is reflected
in all directions, as shown in FIG. 4. Due to the variety of
surfaces, light is reflected in many directions, unlike light
reflected from a mirror. The remainder of the light is refracted as
it enters the layers, where it is scattered due to internal
reflection, or reflection from the surfaces of other layers. Some
of this scattered light is emitted back into the air. As the
diffuse reflected light is reflected or passes through the layers,
it becomes weaker if absorption by the layers occurs. This results
in a diffuse reflected spectrum.
[0075] FIG. 5 is a conceptual chart illustrating a process 501 of
an example of a method for distinguishing authorized 3D-printed
objects from non-authorized versions. Printing can be accomplished
either using specifically created software 502 as instructions, or
by creating instructions by first scanning an existing object 509,
generally through the use of light or radiation. Here, creating
instructions from an existing object 509 is considered an attempt
at counterfeiting 510, or at least not an authorized copy, unless
accompanied by an authorization code. In the case where printing
follows software instructions, those instructions could be
authorized (e.g. purchased and downloaded) 503, or they may be
rogue 506, or not authorized for the creation of genuine branded
products or parts.
[0076] Authorized instructions 503, according to the present
invention, include information that directs materials to be added
to the printed object in a special way 504 that can later be
detected with a chemical analyzer, e.g. spectrometer 505. The
spectrometer distinguishes authorized 3D printed Products from
unauthorized 507, 508, using knowledge of the expected material(s)
and its profile, where it is located in the product, and even
quantitative information as to how thickly the expected material is
layered in the product.
[0077] FIG. 6 is a conceptual chart illustrating examples of
methods for placing the layers of taggant into an authorized 3D
product during the printing process 601. Delivery modes include
adding layers to an existing object using 3D printing 602. The
fingerprinting can still be accomplished, using differential
printing media to create a tagged authorized 3D product. In the
preferred embodiment, the added layers are UV-cured resins.
[0078] A use case for adding layers to an object could be adding a
safety fix to an object subject to recall: if the buckle on a child
safety seat contains a sharp area that could scratch a child, the
manufacturer could provide a blueprint and materials to coat the
sharp area. Authorized fixes would allow the seats to be resold;
showing that a fix was unauthorized could protect the manufacturer
from lawsuits.
[0079] The additions, or the whole product, can be printed with 3D
printing but with a spatial separation between the instructions and
the delivering printer, as in a 3D fax machine, or distributed
manufacturing, with simultaneously printed product generated from a
central recipe to one or more non-adjacent 3D printers 603. Again,
the fingerprinting can still be accomplished, using differential
printing media to create a tagged authorized 3D product, in this
case deliverable remotely.
[0080] The differential printing media for fingerprinting can be
added to the product in exactly the same way as the other printing
media, or they can use a different system 604 to ensure, for
example, ease of use or secrecy. For example, they can be delivered
in sealed cartridges akin to the Keurig container system for coffee
and tea. In the case of fused deposition modeling, a syringe can
add taggant alongside a particular filament as it is melted to be
layered onto an object during printing.
[0081] FIG. 7 is a conceptual chart illustrating the manipulation
of data for 3D printer management to create
spectroscopically-authenticable authorized versions 701. Data
monitoring and secrecy may be important to the creation of
authorized versions and the prevention of counterfeiting. Beyond
simply keeping the differential printing media instructions secret
702, the software containing them can be encrypted. Furthermore,
the data regarding which taggants are layered into the print mix,
and how, can be monitored and tracked so as to preserve secrecy
703.
[0082] To describe this in a different way, an additive
manufacturing apparatus with at least two feedstocks uses a data
file with an encrypted portion, which the user cannot read, to
determine which feedstock is used at what stage of the
manufacturing. The data file may direct the apparatus to use
analytical means such as spectroscopy to check the second
feedstock.
[0083] FIG. 8 is a conceptual chart illustrating mix-layer-color
variant manipulation as examples of methods for distinguishing
authorized 3D-printed objects from non-authorized versions 801.
Fingerprinting can be varied with several different techniques and
validated with one or more analytical devices 802. For example, it
is possible to mix in an additional printing medium as a taggant
803 and then print 804, or reuse a printing medium but in different
layers 805 or in a different location on the product. It is also
possible to vary the curing methods. For example, some printing
media are cured using heat, others using ultraviolet light (UV).
Some existing printers use only one type of cure 806, 809, but it
is certainly possible to employ more than one 807, 810, and it may
be beneficial for fingerprinting purposes to use materials that
have different cure types.
[0084] Color or color combinations can be used as taggants 808, and
not merely in such a way as to be visible to the naked eye. A color
layer may be incorporated in an obscure place, in the same way that
a blue credit card may have a green edge for enhanced
anti-counterfeiting protection. Color may be used in ways that are
scarcely detectable by a human, but show up in spectra beyond the
visible region.
[0085] The 3D Systems ZPrinter, for example, prints in multiple
colors, automatically monitoring print color canisters and
cartridges.
[0086] The 2014 Stratasys Objet500 Connex3 uses triple jets to
create three distinct materials in one build tray, for multiple
mixes of materials and colors. With 14 base materials, up to 82
material properties can be included in a single build, with
16-micron layer thickness. Material options include over 1000
digital materials and base resins to choose from. The ability to
spray resins from multiple jets, and then cure them with UV light,
facilitates the layered anti-counterfeiting taggant approach
described here.
[0087] The 2011 Objet Connex Multi-Material 3D printer uses
16-micron layers. FullCure resin is loaded in cartridges. To date,
these multi-material printers have aimed at colorful prototypes
and, for example, plastic objects with rubberized handles. The
innovation proposed here is to leverage the availability of
multiple materials for anti-counterfeiting and detect them with a
spectrometer or similar device 802.
[0088] The 2010 Polyjet Connex500 uses resin-based rigid materials
to simulate ABS plastic, along with soft material options and
includes four material types and two UV curing lights.
[0089] In one embodiment, the taggant can be cured with lights that
are integrated into the application nozzles. In another embodiment,
one or more curing lights can function separately from the
nozzle(s) layering down the media.
[0090] FIG. 9 is a conceptual chart illustrating the manipulation
of data for 3D printer management to create
spectroscopically-authenticable authorized versions that carry
useful data 901. By encoding information such as date, the spectral
fingerprint can carry data. For example, a particular mix (and
location, thickness, and so on) of printing media can be linked to
a date and location of manufacture 903, as a kind of covert tag.
The tagging scheme can be set to vary, using one of several
methods. For example, as part of the scan-to-copy process, taggant
ratios can be varied so as to create a mix of printing media that
can be interpreted as information-carrying 902. In another
embodiment, using Beer's Law, taggants or taggant mixes can be
distributed in different layers, so the matrix can absorb or
transmit infrared or other radiation in such a way that the path
length-dependent concentration relationship can be varied by
varying the position in the layer or layers 904. Use of Beer's law
with transparent and translucent objects produced by 3-D printers
is feasible via number of taggant-containing layers that are built
up, and also by location in a given layer by taggant pulsing as the
layer is fed thru the appropriate nozzle or nozzles. This can
provide a two- or three-dimensional distribution matrix for
taggants.
[0091] Furthermore, the taggant layer mix can be programmed to
change over time 905, for example to date-stamp the product, or
simply to keep ahead of counterfeiters.
[0092] In one embodiment, the data encoding can be employed with a
printer such as the Optomec Aerosol Jet (2012), because it can
dynamically mix materials on the fly during the deposition process,
including functionally graded materials (gradual switch from 100%
one material in one area to 100% another material in another).
[0093] FIG. 10 is a conceptual chart illustrating cure manipulation
as examples of methods for distinguishing authorized 3D-printed
objects from non-authorized versions 1001. Cure options may be
manipulated in order to make it easier to deliver various printing
media for fingerprinting. For example, the product may remain fixed
but the curing device can move or be varied 1002, e.g. by shining a
light or applying heat at a spot or by layer. The printing media
may be delivered by nozzles that move 1003; light may be used in
that case to provide an instant cure, layer by layer, spot by spot.
It is also possible to use a belt to move the product, relative to
the printing media and curing device(s) 1004.
[0094] FIG. 11 is a conceptual chart illustrating structuring
manipulation as examples of methods for distinguishing authorized
3D-printed objects from non-authorized versions 1101. Structuring
methods may be further varied as well. For example, layers may be
applied to objects that are either transparent or not transparent
in the visible region of the electromagnetic spectrum 1102. In this
case focused x-ray fluorescence spectroscopy may offer the best
choice for authentication 1103. Again, using Beer's Law, taggants
or taggant mixes can be distributed in different layers, so the
matrix can absorb infrared or other radiation in such a way that
the path length-dependent concentration relationship can be varied
by varying the position in the layer or layers 1105.
[0095] Mid-IR reflection spectrometry can be employed with smooth
surfaces and films, where the object is not sufficiently
transparent for absorbance measurements. Specular reflection and
attenuated total reflectance techniques are appropriate with these
types of samples. Beer's law is obviously not relevant with these
types.
[0096] For some applications, for example biological implants, it
will be desirable to have internal structures or channels 1104.
These, too, can be fingerprinted and validated, as follows: use
differential printing media to mark internal structures or channels
so flow can be monitored spectroscopically. Note that since most
bioprinting media have a gel-like consistency, scaffolding,
removable or otherwise, is often part of the 3D printing process.
The anti-counterfeiting fingerprint can be in the removable
scaffold, or it can be embodied in the relative density of the
materials vs. flow channels, for example, by exploiting the
sensitivity of near-infrared spectroscopy to density and particle
size.
[0097] Porosity, channels, density and strand diameter variations
can also be used as taggant methods, where the detecting instrument
(e.g. a near-infrared spectrometer) measures material density or
layer thickness. Such printing is possible, for example, with the
EnvisionTec 3D-Bioplotter (2014).
[0098] FIG. 12 is a conceptual chart illustrating a process of an
example of a method for distinguishing authorized 3D-print media
from non-authorized versions, along with enforcement options 1201.
It may be desirable to authenticate the printing media 1202 as well
as the resulting product, and in some cases there may be a feedback
loop between the two 1205. It may be desirable to keep the taggant
information secret from the printer user 1203, encrypting it into
the software instructions to the printer. To validate that the
printing media are authorized (akin to a printer checking for
authorized printer ink), a spectrometer may be incorporated into
the holding container through which printing media are dispensed
1204.
[0099] To describe this in a different way, an additive
manufacturing apparatus with at least two feedstocks uses
programmable means to determine which feedstock is used at what
stage of the manufacturing. The programmable means may direct the
apparatus to use analytical means such as spectroscopy to draw on
the second feedstock only if certain conditions are met.
[0100] There are several possible ways, often involving software,
to enforce the use of authorized printing media. Some may be
positive: for example, if the media are genuine, the printer
creates a positive authorization 1210, potentially including a
visible mark, such as AUTHORIZED, GENUINE, or similar mark 1209.
Others may be negative: the printer may create a mark indicating
UNAUTHORIZED, FAKE, or similar 1206, 1207. Or the printer may
intentionally create a failure 1208, e.g. a misaligned piece.
[0101] Checking for authorized media can be combined with checking
for authorized instructions. For example, a weight-bearing part may
need to be created using special heavy-duty printing media, and if
the medium is wrong, the part is unauthorized because it may fail
in use. In case of a mismatch between the authorized recipe and the
authorized print medium, the printer fails to print 1211, 1212, or
fails to print more than one copy (e.g. for personal use rather
than resale) 1213.
[0102] An additional benefit of communication between the
spectrometer and print controller is the ability to customize print
instructions for different media. The current state of the art
requires user manipulation of parameters in order to reset print
conditions (such as distance and curing time). The spectrometer can
"read" the print media directly and generate computer commands as
managed by software in the printer, to enable the printer to adjust
automatically. Thus it is possible to provide, for example, an
updated formulation of a resin that, via the spectrometer,
essentially sets its own new print conditions, a considerable gain
in convenience.
[0103] FIG. 13 is a diagram illustrating an example of a system for
authorizing or prohibiting 3D scanning of non-authorized versions
of a 3D object. Scanning and unauthorized copying may be inhibited
with an overt or covert mark on an authorized product 11 that is
interpreted by the scanner 13 or 3D printer. In this use case, a
small QR (quick response, machine-readable) or texture code 12
appears on a genuine product but sends a signal interpreted by a
scanner to inhibit or limit 3D copying. Furthermore, the code can
identify and communicate via the Internet with interested parties,
or indicate that it requires an authorization code to continue.
[0104] To describe this in a different way, a 3D scanner generates
a data file indicating the 3D shape of a scanned object, and reads
an indicator mark, which may be a QR (quick response) or texture
code, which causes it to let the user know, to stop the scan,
and/or to let others know. In other words, a 3D scanner is used to
generate a data file indicating the 3D shape of a scanned object,
and read an indicator mark, which may be a QR (quick response) or
texture code, causing it to let the user know, to stop the scan,
and/or to let others know.
[0105] FIG. 14 is a diagram that illustrates a device for
monitoring the use of authorized print media in a 3D printer, along
with enforcement options. A 3D printer, in particular one using
UV-cured resins for stereolithography, can use a spectrometer 14
for multiple purposes. The spectrometer, in the preferred
embodiment a near-infrared or Raman spectrometer mounted so that it
can validate liquid photopolymer resin 15 through a sapphire window
16 into a vat 17, can authenticate the resin, and, once
authenticated, can convey print parameters 18 to the scanner 19 and
3D printer without the need for human operator intervention. Such
parameters may include distance to the light source, cure time,
particular wavelengths for ultraviolet light curing using a laser
beam 21 from a laser 20, and so on. In addition, the spectrometer
can be used to enforce the use of authorized printing media by
causing positive or negative results as noted above.
[0106] To describe this in a different way, an additive
manufacturing apparatus has a spectrometer monitoring a feed stock
area, passing and information and taking action based on the
information, including marking or changing the piece being
manufactured. In other words, in one example, a UV-curing additive
manufacturing apparatus uses a spectrometer monitoring a feed stock
area to determine UV curing characteristics including duration,
distance, and wavelengths.
[0107] Detection of the taggant or differential print media is
accomplished using an analytical instrument, which is in the
preferred embodiment a handheld spectrometer. The following section
explains the types of spectroscopy that can be used to detect
differential materials, including plastics and beyond, both on the
outer layer of a 3D-printed object and also, in certain cases, in
inner layers. For example, Raman microscopy can analyze multilayer
polymer films. Conventional Raman microscopy, which has spatial
resolution as small as a micron, can analyze cross sections of
multilayer polymer films. Confocal Raman microscopy can generate
depth profiles of the multilayer films, with no requirement for
cross sectioning.
[0108] FIG. 15 is a diagram illustrating authentication of a
3D-printed object 26 using near-infrared (NIR) spectroscopy. NIR
spectroscopy is based on the molecular overtone and combination
vibrations arising from the fundamental molecular vibrations of the
mid-infrared (Mid-IR) region of the electromagnetic spectrum.
Detection of diffusely reflected NIR energy occurs when energy
arising from an incandescent light source 23, is attenuated by a
monochromator 24, reflected from the outermost surface layers of
solid materials, in this case of a 3D-printed object 26, and
interacts with an instrument consisting of a detector 25 composed
of silicon and a composite of indium and gallium arsenide (InGaAS)
materials.
[0109] To describe this in a different way, an object created by
additive manufacturing is tested for authenticity using
non-destructive analysis such as spectroscopy. One material in the
object has a first value when subjected to non-destructive analysis
such as spectroscopy, and a second material, although it looks
similar to the human eye, has a different, second value when
subjected to non-destructive analysis. Subjecting the materials to
non-destructive analysis indicates information such as the
authenticity of the object.
[0110] In other words, an authenticity determination method can be
used for an object created by additive manufacturing, with one
material having a first value when subjected to non-destructive
analysis such as spectroscopy, and a second material with a
different, second value when subjected to non-destructive analysis,
and then more of the first material, making the second material
invisible to the human eye. The second material when subjected to
non-destructive analysis indicates information such as the
authenticity of the object.
[0111] FIG. 16 is a diagram consisting of a graph 27 of the
near-infrared spectra of authentic 34 and counterfeit 35 3D-printed
objects. The degree to which materials absorb and reflect NIR
energy is a function of harmonic and anharmonic quantum
oscillation, Fermi Resonance, Darling-Dennison Resonance, and the
Local Mode Concepts, which taken together describe the NIR
absorption spectrum 27. Because the molecular overtone and
combination bands observed in the NIR spectrum are typically very
broad, leading to complex spectra, it can be difficult to assign
specific features to specific chemical components. Multivariate
(multiple variables) calibration techniques (e.g., principal
component analysis, partial least squares, or artificial neural
networks) are often employed to extract the desired chemical and
physical information from the spectra. Careful development of a set
of calibration samples and application of multivariate calibration
techniques is essential for near-infrared analytical methods.
[0112] FIG. 17 is a diagram illustrating authentication of a
3D-printed object 26 using ultraviolet and visible (UV/Vis)
spectroscopy. UV/Vis spectroscopy is based on electronic
transitions of the atoms that constitute the molecular structure of
materials. When a photon from a light source 23 strikes an electron
in an atom, the photon is absorbed, causing the electron to
transition from the ground state to an excited state. This is then
passed to the detector 25. For detecting tagged 3D printed objects
26, different substances will absorb differently: molecules
containing it-electrons or non-bonding electrons (n-electrons) can
absorb the energy in the form of ultraviolet or visible light to
excite these electrons to higher anti-bonding molecular orbitals.
The more easily excited the electrons (i.e. lower energy gap
between the ground state to the excited state molecular orbital),
the longer the wavelength of light it can absorb. Light wavelengths
are manifested as color (400 nm to 800 nm or violet, indigo, blue,
green, yellow, orange and red) in the visible region, and as
ultraviolet radiation (190 nm to 400 nm) in the ultraviolet region,
after attenuation by a monochromator 24 resulting in UV/Vis
spectra.
[0113] FIG. 18 is a diagram consisting of a graph 28 of the UV/Vis
spectra of authentic 34 and counterfeit 35 3D-printed objects.
[0114] FIG. 19 is a diagram illustrating authentication of a
3D-printed object 26 using fluorescence spectroscopy. Fluorescence
occurs when an orbital electron of a molecule, atom or
nanostructure relaxes to its ground state by emitting a photon of
light after being excited to a higher quantum state by some type of
energy source 23. Detection by a detector 25 of the tagged 3D
printed object 26 occurs when the energy of excitation and emission
is attenuated by the excitation monochromator 29a and emission
monochromator 29b and multiplied by the photomultiplier 30 that
results in a fluorescence spectrum.
[0115] FIG. 20 is a diagram consisting of a graph 31 of the
fluorescence spectra of authentic 34 and counterfeit 35 3D-printed
objects.
[0116] FIG. 21 is a diagram illustrating authentication of a
3D-printed object 26 using x-ray fluorescence spectroscopy (XRF).
XRF occurs when electrons are displaced from their atomic orbital
positions, releasing a burst of energy that is characteristic of a
specific element. Detection is performed by a detector 25 on the 3D
printed object 26. An x-ray fluorescence image processor consisting
of a microscope and CCD camera 36, an x-ray tube 37, an x-ray
filter 38 and a capillary lens 39 is used to capture and process
the resulting image. Detection occurs when the energy from the
source 23, interacting with a 3D-printed object 26, results in an
x-ray fluorescence spectrum.
[0117] FIG. 22 is a diagram consisting of a graph 32 of the x-ray
fluorescence spectra of authentic 34 and counterfeit 35 3D-printed
objects.
[0118] FIG. 23 is a diagram illustrating authentication of a
3D-printed object 26 using Raman spectroscopy. The Raman effect
occurs when incident photons interact with molecules in such a way
that energy is either gained or lost so that the scattered photons
are shifted in frequency. Such inelastic scattering is called Raman
scattering. Detection by a detector 25 of the tagged 3D printed
object 26 occurs when the energy from the source 23, processed
through a lens 41 and filter 40, is attenuated by the monochromator
24, resulting in a Raman spectrum.
[0119] FIG. 24 is a diagram consisting of a graph 33 of the Raman
spectra of authentic 34 and counterfeit 35 3D-printed objects.
EXAMPLE 1
[0120] [NIR Spectroscopy] An article of manufacture was created
using a UV-cure resin 3D printer, as shown in FIG. 25. Such a
printer cures the workpiece by directing UV lights of various
wavelengths at a moveable platform in a vat 91 of resin 92,
exposing liquid polymer resin and then curing it layer by layer.
The UV-curable resin was formulated using urethane acrylate added
to a mix of photoinitiators in the UV longwave and shortwave range.
The workpiece layers of untagged resin were cured, the untagged
liquid resin was removed, and the tagged resin was placed in the
tray for curing of subsequent layers 109. In this case the
near-infrared-active resin was formulated as a homogeneous mix; in
the case of a UV-curing 3D printer with multiple jets for resin
delivery rather than a vat of liquid, taggant would be employed in
one or more jets rather than as a homogeneous mix.
[0121] 3D printing was carried out, building up a block of solid
material 101 with a cross section as shown in FIG. 26. Part of the
workpiece was created using a separate tray of standard, untagged
UV-curing resin, placed into the vat. After the block was printed
it was subjected to NIR spectroscopy.
[0122] Electromagnetic radiation emitted from polychromic radiation
source 107 in the wavelength range from 320 nm to 2500 nm impinged
upon the block at area 104 along path 105 toward the block, area
104 being the urethane acrylate and photoinitiator blend. Diffuse
reflectance path 106 brought near-infrared radiation in the range
of 800 nm to 2500 nm to indium gallium arsenide (InGaAs) detector
108, creating peaks in the target range but no single peak at 1200
nm. The spectrometer was then moved laterally (to the right in FIG.
26) so that the spectroscopic analysis was carried out at area 109.
The value for near-infrared radiation in the range of 800 nm to
2500 nm contained a peak in the range of 1200 nm. In this way the
presence of the tagged resin was detected and confirmed.
EXAMPLE 2
[0123] [UV/Vis] An article of manufacture is created using a
hot-melt-plastic 3D printer with two nozzles. One nozzle extrudes a
conventional polycarbonate. The other nozzle extrudes a specially
blended polyethylene terephthalate to which kaolin has been added
to a concentration of about ten percent by weight. Such a printer
feeds a thin flexible rod stock from a spool into the hot nozzle
for extrusion to the workpiece. The conventional polycarbonate
feedstock is commercially available feedstock for conventional
hot-melt-plastic 3D printers.
[0124] 3D printing is carried out, building up a block of solid
material 201 with a cross section as shown in FIG. 27. Part of the
workpiece is created using a separate filament of standard,
untagged polycarbonate. After the block is printed it is subjected
to UV/Vis spectroscopy. Electromagnetic radiation emitted from
polychromic radiation source 202 in the wavelength range from 200
nm to 1100 nm impinges upon the block at area 203 along path 204
toward the block, area 203 being the polycarbonate. Attenuated
total reflection path 205 brings attenuated total reflection
radiation in the range of 200 nm to 1100 nm to detector 206,
creating a peak at 280 nm. The spectrometer is then moved laterally
(to the right in FIG. 27) so that the spectroscopic analysis is
carried out at area 207. The value for UV/Vis radiation in the
range of 200 nm to 1100 nm contains no peaks at 280 nm. In this way
the presence of the tagged resin is detected and confirmed.
EXAMPLE 3
[0125] [Fluorescence Spectroscopy] An article of manufacture is
created using a hot-melt-plastic 3D printer with two nozzles. One
nozzle extrudes a conventional high density polyethylene. The other
nozzle extrudes a specially blended Acrylonitrile butadiene styrene
to which kaolin has been added to a concentration of about ten
percent by weight. Such a printer feeds a thin flexible rod stock
from a spool into the hot nozzle for extrusion to the workpiece.
The conventional ABS feedstock is commercially available feedstock
for conventional hot-melt-plastic 3D printers.
[0126] To prepare the blended ABS, commercially available
ABS/kaolin composite is gravity-fed into a positive-displacement
pump which forces the mixture into a hot die for extrusion into the
thin flexible rod stock needed by the hot nozzles of the
printer.
[0127] 3D printing is carried out, building up a block of solid
material 301 with a cross section as shown in FIG. 28. Part of the
workpiece is created using a separate filament of standard,
untagged high density polyethylene . After the block is printed it
is subjected to fluorescence spectroscopy. Electromagnetic
radiation emitted from polychromic radiation source 302 in the
wavelength range from 200 nm to 1100 nm is attenuated resulting in
radiation at an excitation wavelength then impinged upon the block
at area 303 along path 304 toward the block, area 303 being the
high density polyethylene. Fluorescence path 305 brings
fluorescence radiation in the range of 200 nm to 1100 nm to
detector 306, creating radiation at an emission but not at the
wavelength of 600 nm. The spectrometer is then moved laterally (to
the right in FIG. 28) so that the spectroscopic analysis is carried
out at area 307. Electromagnetic radiation emitted in the range of
200 nm to 1100 nm contains a peak at 600 nm. In this way the
presence of the tagged resin is detected and confirmed.
EXAMPLE 4
[0128] [XRF spectroscopy] An article of manufacture is created
using a 3D metal powder printer. A first layer of stainless steel
powder is placed in a build box, a print head deposits binder for
each layer, a roller applies a new layer of steel powder, the print
head deposits a new layer of binder, and so on. The object is
sintered in a curing oven. In the second stage, the cured model is
infused with bronze powder, and then heated so that the bronze is
infiltrated into the steel. A third material, cobalt, is infused
into a section to serve as a taggant.
[0129] The 3D printing process builds up a block of solid material
401 with a cross section as shown in FIG. 29. As may be seen in
FIG. 29, most of the body of material 402 is stainless steel and
403 bronze. A portion of the material 404 is cobalt. After the
block is printed it is allowed to cool and is then subjected to
x-ray fluorescence spectroscopy.
[0130] Electromagnetic radiation emitted from x-ray radiation
source 407 impinges upon the block at area 405 along path 406
toward the block, area 405 being the stainless steel infiltrated
with bronze.
[0131] In response to x-ray radiation directed along path 406 at
the resulting 3D-printed object, electrons are displaced from their
atomic orbital positions, releasing a burst of energy in the form
of an x-ray along path 408 to x-ray fluorescence detector 409.
[0132] The spectrometer is then moved laterally (to the right in
FIG. 29) so that the spectroscopic analysis is carried out at area
410, releasing a burst of energy in the form of an x-ray that is
characteristic of the taggant element at 6.93 keV, in this way
detecting and confirming the presence of the cobalt taggant.
EXAMPLE 5
[0133] [Raman Spectroscopy] An article of manufacture is created
using a hot-melt-plastic 3D printer with two nozzles. One nozzle
extrudes a conventional ABS (Acrylonitrile butadiene styrene). The
other nozzle extrudes a specially blended ABS to which kaolin has
been added to a concentration of about ten percent by weight. Such
a printer feeds a thin flexible rod stock from a spool into the hot
nozzle for extrusion to the workpiece. The conventional ABS
feedstock is commercially available feedstock for conventional
hot-melt-plastic 3D printers.
[0134] To prepare the blended ABS, commercially available
ABS/kaolin composite is gravity-fed into a positive-displacement
pump which forces the mixture into a hot die for extrusion into the
thin flexible rod stock needed by the hot nozzles of the
printer.
[0135] 3D printing is carried out, building up a block of solid
material 501 with a cross section as shown in FIG. 30. As may be
seen in FIG. 30, most of the body of material 502 is the
conventional ABS. A portion of the material 503 is the blended ABS
containing kaolin. After the block is printed it is allowed to cool
and is then subjected to Raman spectroscopy. Electromagnetic
radiation emitted from laser radiation source 507 in the wavelength
range from 320 nm to 3000 nm impinges upon the block at area 504
along path 505 toward the block, area 504 being the conventional
ABS. Diffuse reflectance path 506 brings near-infrared-midinfrared
radiation in the range of 800 nm to 3000 nm to Raman detector 508,
creating a spectrum but no peak in the range of 2706 nm. The
spectrometer is then moved laterally (to the right in FIG. 30) so
that the spectroscopic analysis is carried out at area 509. The
value for near-infrared-midinfrared radiation in the range of 800
nm to 3000 nm contains a peak in the range of 2706 nm. In this way
the presence of the ABS composite is detected and confirmed.
Exemplary Applications and Uses
[0136] Any production process using additive printing can employ
the invention described herein. The objects produced may be entire
standalone objects, or they may be parts, including replacement
parts, that can be "authorized" using this method for creating
authenticable versions.
[0137] The use of 3D scanners, with easy copying that can create an
identical object in a minutes-long scan-to-copy process raises a
key question: what IS an original? There is a fast-emerging need
for techniques to mark a branded, authentic, authorized version.
The invention described here creates that authorized version in a
chemical, official recipe, in a way that can be authenticated by a
handheld device (spectrometer or similar).
[0138] Tagged versions may be created using "selective deposition"
with different delivery devices for different media (as is
currently done with food, e.g. pesto, cheese). They may use
"selective binding" on a bed of powder; a laser then moves around
to link or cure materials.
[0139] The printing method may include "support material" e.g. a
bicycle hinge, that gets washed away. This is supported using
different solubilities.
[0140] Print materials are already available in infinite blends,
e.g. from the Cornell Creative Machines Lab, and, using this
invention, those blends can be manipulated in authorized ways to
create spectral signatures for authentication.
[0141] Medical uses include custom-printed medical devices or
drugs. Non-therapeutic ingestible objects that could be printed in
authorized versions include Motorola's ingestible password pill and
the like.
[0142] The use of this invention is not limited to 3D printers, but
could instead be employed on an inkjet printer (U.S. Application
20130342592) configured to print on a three-dimensional object.
From 3D Scan to Model
[0143] Before printing a 3D model, customarily encoded as a
standard tessellation language (STL) file, it must first be
processed by a piece of software called a "slicer," which converts
the model into a series of thin layers and produces a file in a
particular format known as a G-code file, which contains
instructions tailored to a specific printer. Several open source
slicer programs exist, including Skeinforge, Slic3r, KISSlicer, and
Cura.
[0144] The 3D printer follows the G-code instructions to lay down
successive layers of liquid, powder, paper or sheet material to
build the model from a series of cross sections. These layers,
which correspond to the virtual cross sections from the CAD model,
are joined or automatically fused to create the final shape. The
primary advantage of this technique is its ability to create almost
any shape or geometric feature.
[0145] Materials currently are compatible only with certain 3D
printing methods (e.g. UV cure uses thermoplastic resins), but it
is possible that future AM will allow multiple methods and more
mixes of materials. Some materials currently useful for 3D
printing, and therefore available as taggants or markers in this
invention, include but are not limited to:
[0146] Thermoplastics such as acrylonitrile butadiene styrene
(ABS), polycarbonate (PC), polylactic acid (PLA), high density
polyethylene (HDPE), carbon-infused ABS, PC/ABS, nylon,
polyethylene terephthalate (PET), polyphenylsulfone (PPSU) and high
impact polystyrene (HIPS), HDPE; thermoplastic elastomers,
thermoplastic urethanes; granular materials such as PA, PA-GF,
Rigid GF, PEEK, PS, Alumide, Carbonmide; eutectic metals, edible
materials such as icing, dough or chocolate, Rubber (Sugru),
Modeling clay, Plasticine, RTV silicone, Porcelain, Metal clay
(including Precious Metal Clay), ceramics, metal alloys, cermet,
metal matrix composite, ceramic matrix composite, cobalt chrome
alloys, stainless steel, aluminum, PLA mixed with wood fiber, brick
mix, sand, glass, concrete, electrical ink, bio-materials, carbon
fiber, wax, plaster, paper, metal foil, plastic film, pelletized
materials, photopolymers.
[0147] All are compatible with at least one of the spectroscopic
authentication techniques described herein.
[0148] In the case of extruded thermoplastic filament,
anti-counterfeiting taggant could be added to the object using a
syringe injector as part of the extruder, or simply as a defined
pattern of extruded filament materials in particular layer(s) and
position(s) on the 3D-printed object.
[0149] It is also possible to ensure authenticity (of the recipe,
material, or both) by manipulating the curing lights, as described
herein. In photo-polymerization, a vat of liquid polymer is exposed
to controlled lighting under safelight conditions. The exposed
liquid polymer hardens. The build plate then moves down in small
increments and the liquid polymer is again exposed to light. The
process repeats until the model has been built. The liquid polymer
is then drained from the vat, leaving the solid model. The
EnvisionTEC Perfactory is an example of a DLP rapid prototyping
system. In this case, the simplest anti-counterfeiting tagging
method is to mix a spectrally-detectable taggant into one of the
liquid polymers.
[0150] Inkjet printer systems like the Objet PolyJet system spray
photopolymer materials onto a build tray in ultra-thin layers
(between 16 and 30 .mu.m) until the part is completed. Each
photopolymer layer is cured with UV light after it is jetted,
producing fully cured models that can be handled and used
immediately, without post-curing. The gel-like support material,
which is designed to support complicated geometries, is removed by
hand and water jetting. It is also suitable for elastomers.
[0151] The Objet 1000 can deliver 120 different materials, any of
which can be manipulated to serve as layered under-the-skin
anti-counterfeiting taggants on part or all of the 3D-printed
object.
[0152] The taggant in the spray photopolymer case could be simply
one or more of the print materials, in a particular layer or layers
in a particular location or locations on the printed object.
[0153] Ultra-small features can be made with the 3D
micro-fabrication technique used in multiphoton
photopolymerization. This approach uses a focused laser to trace
the desired 3D object into a block of gel. Due to the nonlinear
nature of photo excitation, the gel is cured to a solid only in the
places where the laser was focused while the remaining gel is then
washed away. Feature sizes of under 100 nm are easily produced, as
well as complex structures with moving and interlocked parts. In
this case, the simplest anti-counterfeiting tagging method is to
mix a spectrally-detectable taggant into one of the gels.
[0154] In the case of powder-based printing, an emerging technique
is to print using glue layers that link the powder into a solid
3D-printed object. Spectrally-detectable taggants can be included
as a glue component in one embodiment.
[0155] Yet another approach uses synthetic resins that are
solidified (e.g. UV cured) using light-emitting diodes at selected
wavelengths (LEDs).
[0156] For Mask-image-projection-based stereolithography, a 3D
digital model is sliced by a set of horizontal planes. Each slice
is converted into a two-dimensional mask image. The mask image is
then projected onto a photocurable liquid resin surface and light
is projected onto the resin to cure it in the shape of the layer.
The technique has been used to create objects composed of multiple
materials that cure at different rates, which provide an
opportunity to incorporate the authentication option described
herein. In research systems, the light is projected from below,
allowing the resin to be quickly spread into uniform thin layers,
reducing production time from hours to minutes. Commercially
available devices such as Objet Connex apply the resin via small
nozzles.
Finishing
[0157] Though the printer-produced resolution is sufficient for
many applications, printing a slightly oversized version of the
desired object in standard resolution and then removing material
with a higher-resolution subtractive process can achieve greater
precision. Ensuring authenticity of the recipe can also be enforced
during the subtractive finishing process.
[0158] In the office paper and cutting process used by Mcor
Technologies Ltd, a tungsten carbide blade cuts the shape, and
selective deposition of adhesive and pressure bonds the prototype.
Here, too, authenticity can be assured as part of the finishing
process, e.g. through management of the adhesive.
Food and Medicine
[0159] Cornell Creative Machines Lab has produced customized food
with 3D Hydrocolloid Printing. Professor Leroy Cronin of Glasgow
University proposed, in a TED Talk, that it should one day be
possible to use chemical inks to print medicine. In both cases it
will be extremely important to ensure that the ingredients are
real, and in the case of medicine, mixed correctly. Medicine
depends not only on an active pharmaceutical ingredient (API), but
on the correct delivery of that API, generally as dissolved in the
small intestine. Layering and particle size affect dissolution (and
therefore dosing), and can be monitored using spectroscopy. In this
case the invention protects not only from ingredient failures but
also from potentially dangerous mix mistakes.
Mass Customization
[0160] The invention can require certain features to be
authenticated while others may be permitted to vary, for local
customization options. For example, a user could print an
authorized version of a Mickey Mouse hat, with authentication
features as in the invention, but with variable size to fit
different heads.
* * * * *
References