Your Sticker, Label and Inlay options
NFC.Today refers to ‘NFC Tags’ as stickers (also called labels) and inlays. We call wristbands, keyfobs, pens and so on as ‘NFC Products’. NFC Tags are available in a large number of different construction formats. To make things trickier, different manufacturers and retailers will refer to the options in slightly different ways. However, to keep things clear on NFC.Today, we define the various NFC Tag formats as follows :
Dry inlays are the most basic tag. The dry inlay is simply the antenna etching applied to a film of plastic, usually PET. There’s no adhesive, and the antenna is exposed. Dry inlays can be used as the basis for all other NFC tag formats. Typically, the tags are not separated. Dry inlays are usually supplied with many tags on one continuous piece of plastic either as a sheet or on a roll. On a sheet, they may be used to create sheets of ‘smart’ cards. On a reel, they would usually be converted into NFC stickers.
Sealed Dry Inlay
NFC.Today define the Sealed Dry Inlay as a version of the Dry Inlay which has an additional layer of PET applied to exposed antenna side. This is a non-adhesive format. It’s typically supplied on a single reel so the tags themselves need to be cut/separated. This sealed product is typically used within the construction of other NFC products such as clothing labels.
NFC.Today define the Wet Inlay as particular construction whereby the adhesive is between the exposed antenna and the release liner (backing paper). Essentially, it’s the Dry Inlay with adhesive applied to the exposed side. It’s the thinnest ‘sticky’ option as it contains only a single PET layer. However, the antenna is not protected. A typical use case for this tag may be integration into ‘smart’ business cards. This is because when laminating tags between cardboard, you want the thinnest possible tag so it doesn’t show through. The layers of card on either side of the tag would then provide additional strength and protection to the exposed antenna and chip.
Clear Sticker (Clear NFC Tag)
Clear stickers/labels are a very popular NFC tag. They have a completely sealed antenna with PET on both sides and an adhesive layer. The PET is clear so that the antenna is visible. This strong, protected construction creates an NFC tag that can be used in a very wide variety of applications. The clear plastic displays the antenna and the chip which can look great. However, the surface can’t be ID printed or over printed easily.
White Sticker (White NFC Tag)
One of the most common NFC tags. A very common option with the same construction as Clear Sticker but the upper PET layer is white instead of clear. The white layer allows for printing and ID marking.
Printed Sticker (Printed NFC Tag)
This is a little tricky to define as there are a number of ways of making up a printed NFC label. However, in it’s simplest format, it’s construction is the same as the Clear Label or White Label and the top PET layer is replaced by either a printed paper or printed polyester layer. Optionally, there may be another very thin layer on top as a laminate to protect the printed layer.
This is a special construction to allow the NFC tag to be placed onto metal surfaces. In this type of tag, a thin layer of usually ferrite foil material between the tag and the adhesive layer acts as a ‘barrier’. The exact method of how this is done depends on the tag itself. Ferrite foil is very expensive and the antennas of the tags have to be tuned to exactly match the ferrite material. This means that on-metal tags cost substantially more than normal stickers. They are usually much thicker as well because of the ferrite and there will always be a scan distance reduction compared to a similar non-metal tag. In short, you do not want to use an on-metal sticker unless you really have to.
Reverse On-Metal Sticker
This is a particular type of on-metal NFC tag that was originally pioneered by the Seritag’s founders at RapidNFC. It was designed for use behind smart posters placed inside metal containers. A typical use case being the placement of tags inside bus stop timetable stands and similar locations. The layers are reversed so that the sticker can be applied on the back of the poster and have the ferrite foil barrier facing back behind it.