Cleanroom Scanner
Uses Nanofiber-Based Plastics
 Nanofiber
resin viewed at 2000X magnification
Key to reducing the hazards of ESD in a cleanroom barcode scanner
is the selection of minimally conductive materials for the housing. In the case of
Codestar Electronics, Inc., the engineers selected resins from Hyperion Catalysis
International that contain Graphite Fibril nanofibers. The physical and electrical
properties that these microscopic fibers impart to PC, PBT and other resins offer critical
advantages over conventional carbon fibers.
The body of the Codestar ESD CLEANSCAN scanner uses Hyperion's SR
625-PC, while the trigger is molded from SR 525-PBT. Both resins produce surfaces with the
appearance and smooth tactile qualities of unfilled plastics. The SR designation refers to
the resins' slough-resistance -- larger carbon fibers are more prone to breaking off
during the finished product's usage, generating particle contamination. The problem is
minimalized by reducing the carbon fibers to microscopic size -- the Graphite Fibril
diameter is just 0.01µ in. The nanofibers also disperse more uniformly throughout the
resin, leaving the finished part free of ESD hotspots.
Hyperion says the resins' molding characteristics and physical
properties are essentially the same as those of their unfilled neat counterparts. This is
due to greatly reduced loadings required to achieve ESD surface resistivity versus
conventional carbon-fiber-based products. This translates into lower fill pressures,
reduced processing temperatures, and stress-free, non-warping parts. Manufacturers can use
existing molds, tooling, and processing protocols to produce conductive parts suitable for
cleanroom environments.
Hyperion's data for the resins used for the Codestar scanner
indicate a consistent dissapative range of 104 to 106 (ESD S11.11).
Parts from these resins could be certified for Class 10 cleanroom environments though, due
to its other components, the Codestar scanner qualifies for Class 100 certification.
--RM
For more information, contact:
Hyperion Catalysis International, Inc., 38 Smith
Place, Cambridge, MA 02138. 617-354-9678. Circle 415.
Codestar Electronics, Inc., 170 Knowles Dr., Suite
212, Los Gatos, CA 95030. 800-283-7354. Circle 416. |