Making it stick

Adhesives are being developed to help strengthen the integrity of RFID tags so they can realise their potential across a range of industries

Radio frequency identification (RFID) tags could soon be as ubiquitous as barcodes with the help of a new range of adhesives.

The new materials are being used to not only help bond and protect components of RFID tags but also to stick them to a variety of surfaces.
Huntsman Advanced Materials is just one adhesives specialist developing these materials for the RFID market. The company recently began promoting two specialist Araldite-brand adhesives for use in the electronics industry. The adhesives, which are claimed to be resistant to water, heat and cleaning chemicals, have been developed to bond plastic components of RFID tags and give each chip an extra layer of protection.
Huntsman developed the materials for Tagsys – a global supplier of item-level RFID tags and readers. The Araldite XD 4477-1 and Araldite XB5304 adhesives specifically bond together the plastics components of Tagsys’ small and rigid Ario SL tags.

Although most commonly employed for access control and in intelligent transport systems, RFID is rapidly diversifying into other commercial sectors.

For instance, Tagsys’ tags are being used in traceability applications such as professional garment rental, maintenance and management services from industrial laundries.

When compared with barcode labels, businesses argue RFID tags help cut manual handling costs by automating sorting processes and improving the flow and accuracy of electronic information relating to the lifecycle and maintenance of products.

To date, Tagsys has manufactured several million RFID tags using Araldite adhesives.

These tags, made using Araldite XD 4477-1 and Araldite XB5304, are currently being used at several industrial laundries, including in hospitals to help manage the uniforms of doctors and nurses. In such applications, the RFID tag is patched onto the garment and can contain information such as the wearer’s name, the hospital and department they work in, the size of the garment and the number of times it has been cleaned.

It is claimed that the use of RFID tags in this particular application significantly reduces the number of man hours required to sort clothing by hand, helps control theft and can improve overall laundry service productivity by 10 per cent.

The RFID tags are washed with the garment, so the integrity of the component is dependent on the performance of the adhesive. In this and other applications, the tags have to withstand temperature extremes ranging between -40˚C to 150˚C.

Pierre Garnier, industrialisation tag engineer at Tagsys, said that Araldite provided the required levels of resistance needed. ’When our development team realised that it needed to specify an adhesive that could perform under particularly harsh conditions, we knew our best option was to turn to the team at Huntsman,’ he added.

Huntsman claimed that one of the main selling points for its Araldite adhesives is they can be made into a variety of bespoke products. For instance, the company stated that its research and development team changed the design of the adhesive from a three-component system to a two-component solution to meet Tagsys’ RFID needs. This work resulted in two-component, polyurethane-based adhesives that are white, cure quickly and provide good adhesion when used on plastics substrates.

Adhesive specialists at 3M are also developing products for the RFID market. The company recently helped Chinese manufacturer Daily RFID launch a new passive RFID series for on-metal industrial applications such as railway and warehousing.

Coined as the On-Metal Tag Series, the adhesive RFID tags are specifically designed for close quarters checking. It is claimed that this material can be easily affixed to any metal surface with its self-adhesive 3M glue.

Each tag operates at 125KHz or 13.56MHz, which Daily RFID claims makes them a good choice for those industries that require tags to track products containing metal. The RFID metal tags can be read from a range of 40mm to 100mm and up to 60cm using Daily’s RFID reader.

According to RFID research and analysis centre IDTechEx, the RFID market grew to $5.56bn (£3.72bn) in 2009, having almost tripled in five years. The centre projects that the market for passive RFID tags will grow to more than $10bn in sales by 2019.

RFID technology is still developing and there are a vast number of research projects around the world looking into new tag designs and applications. According to IDTechEx, the US is currently leading in the number of RFID research projects followed closely by the UK. China, however, is quickly catching up.

Huntsman, 3M and other adhesives companies are positioning themselves to reap the benefits of this growing industry. Denis Lucine, sales representative for Araldite in France, said: ’RFID technology is having an enormous impact on a variety of different business areas. Its importance is plain to see and it is clear that this is a key new growth area to watch in the future.’

Design essentials

The key facts to take away from this article» New adhesive materials help bond and protect components of RFID tags

» RFID tags can help cut costs by automating sorting processes
» Adhesive performance can affect the reliability of an RFID component
» Adhesive companies are positioning themselves to benefit from RFID growth

What’s new
Fasteners and adhesives

» Joint support
Solar collector manufacturer CLAGE has been using Böllhoff’s RIVTAC joining technology in the development of a lightweight, flat plate collector. Böllhoff is providing the technology for high-strength joining of the collector’s aluminium frame, which is the production step after complete assembly. To avoid structural deficiencies a one-part joining frame was necessary. At high speed, the pneumatic RIVTAC portable hand tool sets a total of eight joint points – two on each corner. It then joins the corners at high strength. The resulting joined corners are compatible with adhesive technology. The frame is fixed in position so that the sealing silicone is not stressed.

» Holding it together
Profil UK has launched the SZB stud, a fast and secure anchor post for plastic or metal clips used to secure trim, insulation, hydraulic pipework or electrical wiring runs to sheet-metal components. The company is marketing the fastener for the automotive industry, electrical equipment or domestic appliances. The fastener features an asymmetric buttress Christmas-tree-style thread that provides push-on/screw-off location for the secondary fasteners. The anchor stud, which is an industry-standard 5mm core diameter and an installed height of 15mm, is dimensionally equivalent to standard welded fasteners.

» Bonding with steel
West Special Fasteners now offers several different grades of lean duplex fasteners to keep up with changes of metals used in the construction industry. It is claimed that the lean duplex stainless steel fasteners offer comparable strengths and corrosion properties to its other fasteners but have a much lower nickel content. According to the company, lean duplex stainless steels have twice the mechanical strength of conventional austenitic and ferritic stainless steels and they have a potential for use in construction.

» Material for metal
Cyberbond is developing Pump-Gel anaerobic adhesives, which are claimed to maximise efficiency and minimise the need for machinery maintenance in facilities. Curing on metal substrates in the absence of oxygen, the Pump-Gel lines of adhesives are designed to deliver metal-to-metal bonds that are resistant to shock and vibration. The company has a platform of chemistries and viscosities to expand the range of bonding applications. Cyberbond claims the Pump-Gel’s chemistry allows it to stay put and not drip. It can also be applied with one hand because of its Pump-Gel applicator.

» Fusion power
ITW Plexus has developed fast-curing 1:1 methacrylate structural adhesives for turbine blades. The adhesives are designed to chemically fuse FRP/GRP, composite stiffener spars and perimeter flange joints. ITW Plexus said its MA560 and MA590 adhesives are also designed to give increased peel resistance and cycle fatigue resistance while reducing damage encountered during transportation. Terom Wind Energy has used the adhesives in a recent application. The company designed and manufactured a small-size wind turbine – the ATBV26 – suitable for low wind speed sites. The turbine manufacturer used the Plexus structural adhesives to bond together finished blade components.