What are the parts of flexible magnetic tape?
Flexible magnetic tape can be magnetised in three ways; axially, diametrically or in the form of a multi-pole magnet.
Axially and diametrically magnetised
An axially magnetised magnetic tape is magnetised through the length of the magnet, whereas a diametrically magnetised magnetic tape is magnetised through the diameter.
Axially magnetised magnetic tape can only attract ferromagnetic materials to either the top or bottom large faces of the magnet which can be used if you need to attach one magnet to another rather than to a ferromagnetic surface. This is particularly useful when creating a magnetic bookmark as the two magnets will attract each other holding the bookmark to the page.
Axially magnetised flexible magnetic tape can be either an A or B profile. This refers to whether the North pole is on the top or the bottom of the flexible magnet. An A profile magnet has the north pole on the top magnetic face, whereas a B profile magnet has the South pole on the top.
These tapes are described in this way to allow you to purchase the two profiles of magnetic tape. This allows the two flexible magnetic tapes to attach to each other without any magnetic resistance. This is particularly useful for when you are using a production planning board, which is a form of magnetic white board where information is constantly moved around depending on the stage of production an object, for example a house, is at during the construction process.
Diametrically magnetised flexible magnetic tape, on the other hand, will attract ferromagnetic materials from either of the two thin sides along the depth of the tape. This is useful for craft projects or fridge magnets where the user does not want a visible seam in between each section.
A multi-pole flexible magnetic tape has only one face magnetised in the form of a multi-pole magnet.
Multi-pole magnets are magnetised in a striped pattern of alternating north and south poles e.g. north, south, north, south.
Multi-pole flexible magnetic tape can have between 2 and 60 magnetic poles per inch. The more poles per inch a magnet has, the greater its holding strength, but the reach of the magnetic field is reduced. This creates a strong magnetic field close to the magnet to give it a greater holding power. Flexible magnetic tapes with a large thickness have fewer poles per inch as the strength is already increased due to their size.
Flexible magnetic tape with adhesive or laminates on one magnetic face require multi-pole magnetisation, due to the barrier the laminate and adhesives create, preventing the magnetic field from escaping through the top of the magnetic tape.
Multi-pole magnetisation allows the flexible magnetic tape to stick to either another multi-pole magnet or to a ferromagnetic material. This would not be possible if the magnet was magnetised in any other way.
The flexible magnetic tape can be laminated on its non-magnetic side, whilst the other side is magnetised in a multi-pole formation. The laminate is attached to the flexible magnet with the help of powerful adhesives; this means that the laminate cannot be removed from the magnet without a large amount of force.
Flexible magnetic tape is laminated with polyvinyl chloride (PVC) to give the tape added strength and stability. PVC is used as the laminate for flexible magnetic tape as it will not crack when it is flexed.
Laminating the flexible magnetic tape also improves the magnet's visual appearance. A non-laminated flexible magnetic tape is a dull brown colour whereas a laminated flexible magnetic tape can come in a large range of colours. This is particularly useful for arts and crafts projects.
The adhesives on a flexible magnetic tape are laminated onto the non-magnetic face of a multi-pole flexible magnetic tape. This means that the magnetic capabilities of the magnet are not affected and allows the magnet to hold onto non-ferromagnetic materials, such as a wooden door.
The type of adhesive used on a flexible magnetic tape is a synthetic adhesive made from acrylic. The acrylic adhesive is high tack which means it is able to hold more securely to different surfaces.
There is also a type of flexible magnetic tape with an added foam layer in between the adhesive and the magnet which can be used on uneven surfaces. This foam layer aids the magnet by forming itself around any lumps and bumps, but keeping flexible magnet level.
To stop the adhesive from sticking to surfaces when the magnetic tape is not in use, a backing tape is used to protect it.