ID Card Overlaminates
Some ID card printers can apply materials to plastic ID cards protect them from abrasion, wear, fading, alternation, and duplication. Overlay varnishes and laminate patches are the most common materials used to enhance ID card durability and security. Card durability has to do with how well the card withstands various forms of stress. "Durability" means resistance to abrasion, which can be produced when passing a card through a magnetic stripe or bar code reader; protection from image fading, which happens when a card is exposed to sunlight; and resistance to the damage results when cards are immersed in water or exposed to chemicals.
Security issues come into play most obviously when ID cards are used for purposes like licensing drivers. Card security means that the ID card can be verified for authenticity; it means a card that is resistant to tampering, alteration, and replication. With the use of protective materials such as laminate patches with holograms, cards can be constructed to make such illegal activities extremely difficult to accomplish.
ID card overlay varnishes can protect cards from some environmental stresses, but have a much shorter life span than laminate patches; and (with the exception of some hologram varnishes) offer very little security. Varnishes are not solid coverings; they have multiple tiny holes through them, which allow dyes to be drawn away from the card. In time this weakness can cause images on cards to blur and fade. The life expectancy of plain plastic cards with an overlay varnish is about 2 years.
ID card laminate patches offer better protection than plain varnishes in terms both of security and life expectancy. A patch laminate is, as its name implies, a polyester patch that is applied to the surface of the card after printing. Laminate patches, most often either .6 or 1.0 mil thick, are applied via a hot roll laminating station. For efficiency and easy operation, laminating stations are usually incorporated into the body of the ID card printer. The life expectancy of a plastic card with a laminate patch is up to seven years.