Wednesday, September 20, 2000
Akron, OH--Without the ability to texture plastic parts, non-metal rapid tools could have an even rougher time competing against aluminum or steel than they already do. But now, a new process from Akron Metal Etching Co. may just give these "soft" tools the finish they need.
Called Prototex, this patent-pending process can impart more than 2,000 standard and custom mold finishes to tools based on stereolithography (SLA) parts. The process, which actually textures a photosensitive polymer that coats the entire SLA part, has two key steps--first, a photographic image of the desired finish is projected on the part, selectively curing the coating; then, a chemical etching removes any uncured coating.
As Akron Metal Etching president Lee Eisinger explains, "The finish is actually built up in relief," with a depth ranging from 0.0005 to 0.015 inch. Once textured, the SLA part can serve as a master for "soft" tools capable of turning out aesthetically and functionally accurate prototypes. In a recent job, for example, Applied Rapid Technologies (Fredericksburg, VA) used a textured SLA part to create a silicone-rubber tool capable of casting urethane prototypes.
But looking beyond prototypes, Eisinger notes his company has also textured parts that served as the basis for production RIM tools. And he reports interest from the automotive, toy, and consumer electronics industries in using the process to create short-run injection molds.
The several thousand available finishes include standard matte, leather grain, complex geometric patterns, and logos. Eisinger also notes that Prototex has achieved a growing success with difficult multi-layer finishes as well. First developed for SLA materials from DSM Somos (New Castle, DE), the Prototex process has also been used to texture a variety of thermoplastics, wood, and unglazed ceramics. More information on the Prototex process can be found at www.textureame.com.