How To Use Standard NFC Sticker Tag On Metal Surface
Standard NFC tags fail to read when placed on a metal surface.
Here is a typical round 8mm adhesive sticker tag that will read with any NFC reader when placed on stone, wood, glass, plastic, paper, and other non-metal surfaces.
Put the NFC tag on metal and it will fail to read.
NFC tags can be purchased to read on metal, commonly called ‘anti-metal’ tags.
To discuss your on-metal NFC-RFID tag solution needs contact a solution specialist.
This post shows how to use a standard NFC tag to read when placed on metal.
The manufacture of NFC tags is done in layers:
- First layer is ‘substrate’, on the substrate a antenna and NFC chip are bonded, this is called the ‘inlay’.
- The inlay is typically covered with paper or waterproof plastic based material like PET (Polyethylenetherephtalate).
- This combination is called a ‘dry inlay’.
- When an adhesive layer is applied to the bottom of the ‘dry inlay’ (or in place of the substrate cover) it becomes a ‘wet inlay’.
If the NFC tags are manufactured in rolls there is also a ‘release liner’ below the adhesive layer.
To make an on metal (anti-metal) tag from a standard tag there needs to be a barrier (or wide separation) between the metal and the inlay.
When an NFC tag needs to be placed on a metal surface it must have a electrically nonconductive barrier between the metal and the inlay.
The material commonly used behind a wireless charging power coil can be used as the barrier to allow an NFC tag to be read on metal. This material presents a ferrite barrier sh
eet EMI anti-interference shield.
With a wet inlay peel the adhesive cover from the tag
and stick it on the anti-metal barrier material.
For limited surface size, the ferrite barrier material can be trimmed to fit the NFC tag.
In this example the anti-metal ferrite
material barrier has an adhesive layer. The adhesive cover is removed as shown above, then the on-metal tag is placed on the metal surface.
Here the NFC tag can be seen mounted on metal water valve for inspection and reference information.
Here is the view of the NFC sticker tag attached to the metal water valve handle, out of sight, yet still available for reading with NFC reader for inspection & reference.