Folienstifte

Folienstifte, also known as overhead markers or transparency markers, are a type of pen designed for use on plastic film surfaces, such as those used with overhead projectors. Their primary characteristic is the ink formulation, which is specifically developed to adhere to and remain visible on smooth, non-porous materials like acetate or polyester film.

The ink in folienstifte is typically alcohol-based or solvent-based, allowing it to dry quickly and prevent smudging on the plastic surface. This is crucial for presentations where the film might be handled frequently or if the projector is positioned in a way that could cause heat to affect the ink. The ink is also often permanent, ensuring the writing or drawing remains legible throughout the duration of the presentation.

Folienstifte are available in a variety of colors, similar to standard permanent markers, allowing for different visual distinctions and emphasis on projected information. The tips can range from fine point for detailed writing to broader chisel or bullet points for larger text and diagrams. While originally intended for overhead projectors, their ability to write on plastic has made them useful for other applications where marking on smooth, non-absorbent surfaces is required, such as labeling plastic containers or creating temporary markings on certain types of packaging.