Permanent marker

"Indelible marker" redirects here. For the indelible supernatural mark on the soul held by Catholics to be imprinted by baptism, see Sacramental character.

The "chisel tip" of a marker

Sanford King Size Permanent Marker

Sharpie brand permanent markers.

A permanent marker is a type of marker pen that is used to create permanent writing on an object. Generally the liquid is water resistant, contains a solvent such as xylene, toluene, or alcohol^{[citation needed]}and is capable of writing on a variety of surfaces from paper to metal to stone. They come in a variety of tip sizes (ultra fine to wide), shapes (chisel point, bullet tip, and wide bristle), and colors (metallic, non metallic, or ultraviolet reactive).

Like spray paint, these markers give off volatile organic compounds and are commonly used in the drawing of graffiti.

Some of the most recently made permanent markers are made from recycled plastic.^{[citation needed]}

The permanent marker was invented in 1952 by Sidney Rosenthal.

Removal

Most brands of "permanent" marker wipe off easily with acetone free nail polish remover, the kind containing ethyl acetate.

These markers are generally not truly permanent, on hard, non-porous surfaces, because instead of staining they form a surface layer that can be removed by high pressure cleaning or paint thinning solvents such as acetone, and they will eventually wear away over time, or fade in sunlight.

Some markers are designed to be long lasting, for instance by having two inks, one specialized to resist solvents, and one specialized not to fade.^{[citation needed]} These can be available in refillable form.^{[citation needed]}

A permanent marker can also be removed by drawing over it with a dry erase marker on certain surfaces such as a whiteboard as it contains acetone^{[citation needed]}.

An alcohol-based product (such as aftershave) and some paper towel is also effective in removing permanent marker. Simply apply the alcohol and wash clean with the paper towel. It works better on smooth, hard surfaces like computers, tile and linoleum.

Use in Microscopy

In addition to being used for labelling microscopy slides, permanent markers can actually be used to do a negative stain of a bacterial sample. This means the background is stained with the marker, but the bacteria are not. The bacteria can be seen because they are stained (lighter) while the background is unstained (darker).