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March 1, 2002

3 Min Read
Materials Update

0302i48a.jpgStrength, heat resistance of PPS improves lighting fixtures
A cost-effective material with properties to withstand harsh environmental conditions was needed to protect landscape light fixtures. Architectural Landscape Lighting (Santa Ana, CA) turned to Ryton for the solution and settled on the company's polyphenylene sulfide (PPS) engineering thermoplastics for use in the housing for its newest landscape lighting fixtures, the Belero and Baby Belero. Ryton-4-200BL was chosen for use in the larger fixture; R-7-120BL was selected for the smaller size. 

The PPS was chosen for its ability to withstand a variety of environmental factors, such as local soil conditions and fertilizers. It was also chosen for its ability to be more highly tooled and to produce more detailed shapes than aluminum. Another factor was the material's high-temperature performance. With a heat deflection temperature of more than 500F, Ryton R-4-200BL is resistant to housing temperatures that can climb to more than 300F. 

The selection of Ryton R-4-200BL and R-7-120BL compounds were well received by molder Artistic Plastics Inc. (Anaheim, CA). "The reasons to change to Ryton PPS are time and money," says Dennis Chadwick, Artistic Plastics president. "Ryton PPS flows in a heated mold like water. It makes an extremely smooth parting line, so after-mold finishing is eliminated, reducing total manufacturing time." Also appreciated was the low shrink rate of the material when it comes out of the mold, enabling the molder to design precise molds to take advantage of its dimensional stability. 

The fixtures were first molded in China, but the complex shape and molded-in curves and grooves caused the project to be relocated to Artistic Plastics. The problem in Asia stemmed from the time required (12 hours) for the mold to reach operating temperature. When it finally got hot enough to mold plastic parts, the mold chronically locked up and couldn't be opened to release the molded part. Artistic says it was able to solve this problem and thereby produce good parts after extensively modifying the three malfunctioning tools employing wire and conventional EDM. 

The light fixture is molded in one piece and designed to be watertight and dust-proof. The glass lens is held in the assembly with three clips and sealed with high-temperature silicone. The lens and visor assemblies are attached to the housing with four stainless steel screws. The larger fixture is 10 inches long with a 7-inch-diameter lens, while the Baby Belero is 8 inches long with a 4-inch-diameter lens. Lens visors are available in 3.25-inch lengths for both and a 7-inch length for the Belero. These lights are expected to find applications in landscape and building accent lighting. 

Ryton PPS, Houston, TX
(877) 798-6666
www.rytonpps.com 

Online billing available at resin e-commerce site 
An electronic invoice presentment and payment (EIPP) system has recently been added to the features of Omnexus, the online resin marketplace. Through an alliance with BillingZone, the site now allows buyers ordering from one or multiple suppliers via Omnexus to conduct their entire procurement process, from initial searches for product availability to invoice presentment and payment, in an automated online environment. 

Omnexus, Atlanta, GA
(678) 302-3438
www.omnexus.com 

BillingZone LLC, Pittsburgh, PA
(412) 705-3000
www.billingzone.com 

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