Scotchlite is made of tiny glass beads, about the size of granules of powder. It is a proprietary product of the 3M company, although they occasionally allow its use by other companies, such as Nike.
Scotchlite's primary function is to be reflective of light. As a bonus, it also helps to reduce friction in applications where two materials must rub against one another due to a product's demands and construction. In some instances, such as speed-skating clothing, this is a useful feature.
Several Scotchlite products are available for various applications. Fabric, trim, high gloss materials (which are attached to a vinyl backing), graphic transfers and inks are available for apparel. Transfer films may be used on rigid items, such as signage. Pressure-sensitive adhesive films may be screenprinted, but 3M does not recommend that they be applied to washable fabrics.
Reflective tire sheeting and vulcanizable film is available for application to rubber, such as running shoes or tires. Finally, SOLAS grade products are water-resistant and are primarily used for safety applications such as life jackets for watersports and outdoor activities.
Scotchlite materials come in a wide variety of colors for most applications. In a completely dark situation, shining light on a material to see if it reflects can show very quickly whether it is Scotchlite or not. Scotchlite is used worldwide, and is the most prevalent material of its kind due to 3M's international saturation.
Scotchlite materials are weather resistant, flame resistant and reasonably abrasion resistant. They will wear over time, as all fabrics do, but will retain varying degrees of reflectivity until they wear out.
Reflectivity is important in many applications. Sports clothing, running shoes, firefighting, construction and many other fields benefit from reflective materials used as safety measures.