Light-activated resin

Light-activated resins are one-part translucent polymers that cure and quickly harden when exposed to specific light spectrums. The required wavelength for cure is specific to the resin chemistry.

The resin remains liquid (thick, like syrup or honey) under normal indoor lighting which allows the user to work with the material until curing is desired. After curing, light-activated resin is denser than air-cured resins due to its inherent chemistry and because no mixing is required that might introduce air bubbles.

Technology

Resin chemistry is tailored by manufacturers to meet specific customer needs. Both visible light and ultraviolet light have been used as curing mechanisms for this technology. Ultraviolet light presents some potential hazards and workers using ultraviolet curing resins generally wear protective equipment.

Uses

Dentists have used visible-light activated resins as adhesives for decades. Resin cements are utilized in luting cast ceramic, full porcelain, and veneer restorations that are thin or translucent to permit visible light penetration and thus polymerize the cement. Light-activated cements may be radiolucent and are usually provided in various shades since they are utilized in esthetically demanding situations.^[1]

Conventional halogen bulbs, argon lasers and xenon arc lights are currently used in clinical practice. A new technological approach for curing light-activated oral biomaterials is presented. The new light curing unit (LCU) is based on blue light-emitting diodes (LED). The main potential benefits of LED LCU technology are: long lifetime of LED LCU (several thousand hours), no filters or cooling fan required, virtually no decrease of light output over lifetime with resulting consistent and high quality of material curing. Simple depth of cure experiments of dental composites cured with LED technology show promising results.^[2]

Industrial facilities are utilizing light-activated resin as a sealant for leaks and cracks. Some light-activated resins have unique properties that make it ideal as a pipe repair product. These resins cure rapidly on any surface, wet or dry.^[3]

Light-activated resins recently gained a foothold with fly tiers as a way to create custom flies, in a short period of time, with very little clean up involved.^[4] Manufacturers also use light curing systems in OEM assembly applications such as specialty electronics or medical device applications.^[5]

Recently, light-activated resins have found a place in floor refinishing applications, offering instant return to service not available with any other chemistry due to the need to cure at ambient temperatures. Because of application constraints, these coatings are exclusively UV cured with portable equipment containing high intensity discharge lamps. Such UV coatings are now commercially available for a variety of substrates, such as wood, vinyl composition tile and concrete, replacing traditional polyurethanes for wood refinishing and low durability acrylics for VCT.

Also used in 3D SLA Printers.

References

This article is issued from Wikipedia - version of the Wednesday, January 27, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.