Technologies for quick & easy shopping


I’m sure I’m not the only one who gets annoyed at long checkout queues and unnecessary delays when shopping.  Recently I have been exploring the use of RFID tagging and other technologies to detect items and enable automated purchases.  We are becoming more familiar with the use of smartphones for banking transactions via contactless (NFC) and being connected everywhere we go.  All these technologies are coming together in ways that make our lives easier but at the same time it can be scary and leave us wondering if we are becoming too vulnerable to cyber crime.

Amazon Technology are exploring ways of changing the shopping experience by trialing a “just walk out” system of shopping nicely explained in their video.  I wanted to explore the technologies they were combining to enable this approach and found that a patent application filed about 4 years ago covers a range of the technologies they are testing in their Amazon Go stores.  As usual the patent application is written in broad terms that can be adapted to a number of scenarios and so the terminology refers to a “material handling facility” rather than a shop.

Date: 8 Jan 2015
Abstract:  This disclosure describes a system for automatically transitioning items from a materials handling facility without delaying a user as they exit the materials handling facility. For example, while a user is located in a materials handling facility, the user may pick one or more items. The items are identified and automatically associated with the user at or near the time of the item pick. When the users enters and/or passes through a transition area, the picked items are automatically transitioned to the user without affirmative input from or delay to the user.

The description in the main body of the patent indicates that the technology can have application in stores, warehouses, libraries, museums, rental centres, etc.

Key enabling technologies are RFID tagging of items, image capture, facial recognition, sensors, wireless networks.  Typical scenarios include a user entering a facility and being identified from a tag or smartphone device, selecting items and various methods are described for detecting when an item has been removed from a shelf and placed in a bag, a log of the items chosen is recorded and when the user exits the facility the transaction is completed – which can be that the user is charged for the items and the amount is deducted from their bank account.

It is possible to track the progress of this application in the Global Dossier and I can tell that the original claims have been rejected; revised claims have been submitted which seek to work around the objections made by the patent examiner.

Phil’s Comments

RFID technology is widely used as a tagging method and the cost per tag has come down dramatically in price through the developments in printed electronics.  Direct printing of RFID on packaging is also possible.  Reliable detection of passive RFID (no built in power source) is better than it was and so every item in a full bag of shopping can easily be detected as one passes a sensor.  This application indicates that a whole range of technologies needs to work together seamlessly to get an automated shopping system working.  The reliance on cameras to aid in the detection of users and items picked is actually higher than I expected, but is also reassuring in that it helps to increase security and offset the concerns that the system could be abused.  The Amazon Go shop in Seattle has been running for about 5 months now but is only open to Amazon employees – I will keep an eye open for updates on its progress.

Please contact me if you would like more detailed patent analysis of this technology area.


Printed Electronics adds security to your Banknotes

Sipca, a company founded in 1927, provides secured identification, traceability and authentication solutions and services.  A core component of their security expertise is the use of security inks that protect the majority of the worlds banknotes.  I was interested to notice that earlier this year they filed a patent application combining the use of security inks with flexible printed electronics features to further enhance the security aspects of banknotes.


The patent application is WO2016037895, published on 17 March 2016, the inventors being Brahim Kerkar and Philippe Amon.

Most recent(amended) claim 1 is:

A banknote comprising: one or more security features, at least two flexible printed electronic (FPE) elements embedded in the banknote, at least one of the one or more security features and at least one of the at least two FPE elements have an interrelationship with each other, and a plurality of the at least two FPE elements have an interrelationship with each other, characterized in that each FPE element contains one or more security features comprising a chemical key represented with a set of molecules having different absorption or emission spectra, preferably said banknote comprising “n” FPE elements and “m” luminescent compounds, providing n*m potential combinations of secure FPEs dispatched in each banknote.

A typical banknote is shown in Fig 2 above (taken from the patent application) and has a variety of features for added security such as a substrate (0), a flag (10) and security features being a serial number (1 ), value numbers (2; 3) (wherein one of said value number is made of a colorshifting ink), an intaglio printed design (4), patterns made of a luminescent ink (5), luminescent fibers (6) incorporated in the substrate (0); a security thread (7), a transparent window (8) and a hologram (9).

The invention describes a banknote which has at least 2 FPE elements and these are designed to relate to each other and to the other security elements to provide the authentication mechanism.  Various modes of operation are described including the ability for the FPE to be capable of additional features such as being configured to interact, for example, with a computer and/or a mobile phone.

One example provided is if a banknote having added FPE features is stolen, the owner, for example, using a mobile phone already containing the data related to the banknote (e.g., in a storage device) can send a communication to (e.g., all banks around the world), identifying the banknote as stolen, to be sure that the banknote is identified as stolen and/or is no longer valid. In other embodiments, the FPE may be operable to send a signal to the owner’s mobile device when a banknote belonging to the owner is used. Thus, if the banknote is stolen, when the thief attempts to use the stolen banknote, the owner is notified, and can contact the police. The embedded FPE may also provide traceability capabilities for the banknote, so that, for example, a location of the stolen banknote can be determined.

Phil’s Comments:

This is a further example of the way flexible printed electronics can enhance the practical usefulness of everyday things.  The examples here also include security aspects which in itself is a huge technology field for the detection of counterfeiting and theft.  The secret is the ability to make these FPE elements small enough and self contained to work over a long period without the need for a separate power source.  Passive RFID elements are now very common and in everyday use.


Aqueous Conductive Silver Ink

Printed electronics is continuing to grow as more and more applications are developed and commercialised.  One of the key stumbling blocks continues to be the practicalities of printing narrow conductive tracks and the ease of use of the materials and processes involved.  One of the key system components, often taken for granted,  is the ink.  The majority of conductive ink compositions in use today are solvent-based thick film systems designed for low speed screen printing.  Water based conductive inks and coatings offer significant ecological advantages over solvent-based compositions, as the latter release solvents into the atmosphere on drying.  Aqueous conductive inks, however, have so far not offered the high conductivity, or low electrical resistivity, achievable with solvent-based formulas.

Sun Chemical Corp. have just been granted a patent for an aqueous ink with high conductivity and good printing properties.  This invention more specifically relates to an aqueous conductive silver ink suitable for use in RFID and other electronic technologies. The composition is highly conductive and requires reduced drying energy. In addition, it may be applied to low cost substrates via high speed printing processes. The key components of the ink formulation include: (meth)acrylic copolymer or salt thereof; conductive particles; an anionic surface wetting agent; defoamer and water.  The first claim suggests the ink can be up to 80% water depending on the amount of the other ingredients.

The patent is US8709288 and it was issued on 29 April 2014.  The Inventors are Jason Rouse and Dave Klein.

The independent claims from the patent are listed below:

1. A method of forming a conductive pattern on a substrate comprising applying a conductive composition comprising (a) metallic silver conductive particles, (b) water soluble styrene/(meth)acrylic copolymer, (c) an anionic wetting agent, (d) defoamer and (e) 10 to 80% water, the composition providing a sheet resistance of less than 0.83 ohms/sq, on the substrate and drying the composition.
34. A method of forming a conductive pattern on a substrate comprising applying a conductive composition consisting essentially of (a) metallic silver conductive particles, (b) water soluble styrene/(meth)acrylic copolymer, (c) an anionic surfactant, (d) defoamer and (e) 10 to 80% water, the composition providing a sheet resistance of less than 0.83 ohms/sq, on the substrate and drying the composition.
37. A method of forming a conductive pattern on a substrate comprising applying a conductive composition consisting of (a) metallic conductive particles, (b) water soluble styrene/(meth)acrylic copolymer, (c) an anionic surfactant, (d) defoamer, (e) 10 to 80% water, and optionally another solvent, the composition providing a sheet resistance of less than 0.83 ohms/sq, on the substrate and drying the composition.

The differences above are subtle but important, claim 34 describes the composition with an anionic surfactant rather than a wetting agent, and claim 37 describes a more general formulation with any metallic conductive particle and optionally includes another solvent.  Each claim includes the requirement that the composition provides a resistance of less that 0.83 ohms/sq on the substrate.


Phil’s Comments:

Good to see that research into inks suitable for printed electronics is providing environmentally acceptable formulations.  Reducing solvents and also reducing the energy requirements for drying are all good directions for the ink design.  We sometimes forget the huge demand put upon the inks we use, for example they need good abrasion and chemical resistance when dried so that they are not easily scratched or wiped off during subsequent uses, they need to have proper rheology and substrate wetting properties to obtain good ink transfer and graphic reproduction. Additionally, the ink should possess good flexibility and thermal stability to withstand the physical deformation to which the substrate may be subjected.  Let’s remember the research that goes into the inks when we next see a printed electronics design in use!


Printed Electronics Patents Granted in 2011 – Conductive Ink

This is the second in the series covering patents granted during 2011 in the printed electronics field.

US7968011: Conductive Ink

Inventor(s): Gerardus Cornelis Overbeek, Michael Arnoldus Jacobus Schellekens, Alfred Jean Paul Bückmann

Assignee(s): DSM IP Assets B.V.

Filed: 6 Mar 2007; Issued: 28 Jun 2011

Abstract: A conductive ink comprising 10 to 75 wt % of at least one solvent comprising ≦20 wt % water; 0 to 50 wt % of at least one radiation curable material having a Mn in the range of from 50 to 10,000 g/mol; 5 to 70 wt % of at least one polyurethane having a Mw in the range of from 4,000 to 70,000 g/mol, 0 to 5 wt % of isocyanate-reactive component(s) bearing ionic or potentially ionic water-dispersing groups and a free isocyanate group content <0.5 wt % and 20 to 85 wt % of a conductive material.

The claims provide more details around the various components but rather than copying the claims I’ll explain in simple English.

The problem being solved by this invention is the lack of a common binder that can be used across a range of different conductive ink materials.  The inventors have provided a polyurethane based binder which they have found can be used to create inks suitable for flexography, gravure and ink-jet printing.  The method does not require high temperature curing and leads to good conductivity. Claim 1 requires that a UV radiation curing material is also included with the binder and this gives additional improvements in film properties and faster printing speeds.

The conductive materials are described as any form of conductive particle and the scope is very broad, including nanoparticles of silver or copper.  The particles can be flakes, fibres, nanotubes or mixtures, the particles can be silver coated.

The system requires a solvent which can be alcohol based (e.g. ethanol, iso-propanol, etc.) or any from a broad range of esters, ethers, ketones, etc. and preferably contains less than 10% water.

Any reader interested in the full formulation should refer to the patent for details of the preferred formulations.

Kovio Inc. patents: Printed Electronics Devices at lower cost


The radio frequency identification (RFID) market is huge, already over £2 billion.  Within this market passive RFID is expected to be the prime candidate for printing but so far the main thrust has been the printing of the antennae.  Often silver inks are used but the price fluctuations of silver (currently very high) cause many companies to look for alternatives such as copper, aluminium and organic conductive polymers.  The expensive part of an RFID tag is the chip and there are not many companies who have tried printing the chips.  Kovio Inc. was the first using nanosilicon on a variety of substrates.

The real advantage of printed RFID is the potential to produce tags and labels cheaply, perhaps even being able to print them directly as is done with barcodes today.  Applications like library tags, that currently use high cost silicon memory chips, tend to use HF rather than UHF and I believe this is where the potential for printed RFID is to be found.

Kovio Patents

Kovio Inc. were recently granted a third patent in a series which all relate to methods for making devices such as RFID tags at lower cost.  The key phrase from their abstract is:

The present invention advantageously provides semiconducting thin film structures having qualities suitable for use in electronics applications, such as display devices or RFID tags, while enabling high-throughput printing processes that form such thin films in seconds or minutes, rather than hours or days as with conventional photolithographic processes.

Their recent series of patents are summarized in the table below:

The most recent patent can be viewed here and has 67 method claims, the earlier patents relate to the materials and the thin film structure.  The 7553545 patent is also interesting in that it details the linewidths and gaps that can be printed.