Technical Insight
Mapping ESD Uniformity Across Parts, Coatings, Films, and Production Lots
A registered spatial and lot-sampling plan for separating within-part, part-to-part, cavity, web, coating, and lot variation in ESD performance.
Author: Aurexene Materials Engineering Team · Last updated: 2026-08-28
Quick Answer
Register measurement locations and production genealogy before testing, use the same method and conditioning at every location, report distributions rather than only averages, and confirm the ESD function at representative nominal and worst-case positions.
Problem
A center-point reading or a lot average can conceal failures at edges, weld lines, ribs, thickness transitions, web margins, coating starts and stops, seams, junctions, and ground contacts. An unregistered point cannot be traced back to material or process evidence.
The sampling plan must separate variation within one unit from unit-to-unit, cavity-to-cavity, run-to-run, web-position, and lot-to-lot variation. Pooling those levels destroys the information needed for release and root-cause decisions.
Mechanism
Local ESD response can change with filler concentration, agglomeration, orientation, contact topology, thickness, skin-core structure, substrate, coating coverage, drying or cure, abrasion, surface contamination, and electrode contact.
A spatial pattern is not a unique mechanism. The electrical map should be aligned with production position and, when needed, thickness, composition, morphology, surface, and process evidence before a cause is assigned.
Tradeoff
Dense maps increase detection power but add measurement time and may disturb sensitive surfaces. Sparse plans should preserve high-risk features and likely gradients rather than reduce the map to convenient center points.
A fixed grid enables lot trending. Feature-based points capture geometry and process effects. A useful control plan often retains both: stable reference coordinates plus named critical features.
Material Strategy
For molded or formed compounds containing Conductive Carbon Black, Antimony Tin Oxide (ATO), Multi-Walled Carbon Nanotubes (MWCNT), Few-Walled Carbon Nanotubes (FWCNT), or Single-Walled Carbon Nanotubes (SWCNT), map flow path, welds, features, thickness, direction, and cavity.
For coatings and films, including routes using SWCNT-nano-Ag or MXene, retain substrate coordinates, coat direction, edge, start and stop, web or panel position, junctions, contacts, and protective layers.
Recommended Architectures
| Map | Required locations | Genealogy to retain |
|---|---|---|
| Molded or formed part | Gate, flow path, end of fill, weld line, rib, edge, thickness transition, cavity, and relevant directions | Compound lot, molding run, tool and cavity, machine settings, cycle position, conditioning, and part orientation |
| Coating or film | Center, edges, start and stop, coat and cross-coat directions, web or panel positions, overlaps, junctions, and contacts | Dispersion batch, substrate lot, coating run, position and time, wet and dry thickness, drying or cure, and finishing |
| Production release | Fixed nominal and risk-based locations across multiple units and the defined sampling hierarchy | Material lot, formulation batch, line and tool, run, shift or time, unit, map, retest, disposition, and change state |
Measurement & Validation
- Draw the coordinate system and name critical features before seeing the data. Record direction for anisotropic surfaces.
- Select surface, sheet, volume, resistance-to-ground, or static-function methods from the intended path. Lock electrodes, voltage, timing, contacts, ground, and conditioning.
- Use reference specimens and repeated locations to separate measurement repeatability from product variation.
- Report location-level results, distributions, outliers, missing points, and uncertainty. Preserve each result's unit, genealogy, and map coordinate.
- Confirm charge generation, static decay, discharge, or installed function at representative nominal and worst-case locations after relevant exposure.
Qualification Boundary
Define the unit, lot, run, tool, cavity, web or panel position, sampling frequency, map coordinates, feature and direction labels, specimen preparation, conditioning, method, electrodes, voltage, time, ground, instrument range, reference controls, repeats, uncertainty, functional checks, acceptance limits, and retest and disposition rules.
Related Products
Related Applications
Related Comparisons
No reviewed comparison page is available yet. Uniformity comparisons require the same registered map, method, conditioning, genealogy level, and functional boundary.
Downloads & Engineering Support
The case study is approval-required process context, not product-, part-, or lot-specific uniformity evidence.
- Request ESD mapping support
- Discuss map design and measurement controls
- Discuss genealogy, sampling, and lot release
What to Validate
The mapping hierarchy and reporting controls are engineering guidance. No uniformity or lot-conformance claim is assigned to a product from Aurexene Materials until approved location-level evidence links the named grade, host, process, construction, method, conditioning, and production genealogy.
Need to apply this boundary to a grade, formulation, test method, or production route? Discuss it with the Aurexene Materials Engineering Team.