Outdoor Lighting and Custom Silicone Gaskets

Written by Katie Sullivan | January 18, 2016 4:00 PM

Outdoor LED lights are subject to a wide range of environmental elements and must be designed to withstand these hazards for the long life of LEDs. There are many components included in an outdoor lighting assembly, and one of the most important elements is a gasket. When choosing a material for an outdoor lighting gasket, it's imperative to understand the mechanics of an outdoor lighting fixture.

Outdoor lighting gaskets are made to protect delicate interior lighting components against rain, moisture, UV exposure (aging), oxidation, ozone, dust, and weather (ice, rain, snow). It's also important gaskets and seals are made from materials that have excellent compression set characteristics.

Compression set is considered one of the most important characteristics to consider when working with foam materials and plays a huge role in the longevity of the fixture. The gasket must be made to last the entire life span of the lighting component which could be anywhere from 5-10 years.

Another important factor is the Ingress Protection rating of the gasket material, which is typically IP66 for outdoor lighting enclosures. IP ratings are important because they give you an idea of what an enclosure is protected against at a quick glance. See our blog post about IP Ratings.

Materials for Die-Cut, Outdoor Lighting Gaskets

Among the numerous materials one could choose for an outdoor lighting gasket application, there are three materials that stand out from the rest:

silicone rubber
silicone sponge
silicone foam

These three advanced materials can withstand outdoor challenges resulting from weather and aging. The material's properties remain unaffected when exposed to extreme high and low temperatures. Silicones are also resistant to hardening and aging from ozone, oxidation, UV, and sunlight. Furthermore, in seeking a flame-retardant material for your outdoor lighting application, silicone materials generally carry a UL 94 V-0 flame rating.

Marian sources silicone foam, sponge, and rubber products from some of the world’s leading suppliers like Rogers Corporation and Saint-Gobain and can readily custom fabricate gaskets with adhesive lamination utilizing rotary die-cutting, water jet cutting and plotter cutting.

Bonding an Adhesive to Silicone for Sealing

A laminated adhesive may be required for bonding the outdoor lighting gasket to the housing. When selecting an adhesive, it requires you to have an understanding of the housing surfaces that will be bonded. Different surfaces require different adhesive systems.

For example, if you were to bond the gasket to an unpainted aluminum enclosure, you would need to look for a high surface energy pressure sensitive adhesive, but if there is a powder coated finish added to your enclosure, you'd need a low surface energy pressure sensitive adhesive. See our blog post about surface energy.

Since silicone is a low surface energy material, it can be difficult to bond to other materials or substrates. Marian also has the capability of corona surface treatment to the silicone material to increase the surface energy of the silicone to allow for attachment to other high-surface energy materials.

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