Technical Insight

ATO Dispersion Design for Solventborne Acrylic and PU NIR Coatings

A formulation and qualification framework for Antimony Tin Oxide (ATO) dispersions in solventborne acrylic and polyurethane coatings, covering solvent compatibility, letdown stability, cure, optical response, and durability.

Author: Aurexene Materials Engineering Team · Last updated: 2026-08-28

Quick Answer

Qualify Antimony Tin Oxide (ATO) in the complete solvent, resin, and cure package. Stability in a carrier solvent alone does not show that the dispersion will survive acrylic letdown or a reactive polyurethane formulation.

Problem

An ATO concentrate can flocculate, thicken, seed, or settle after resin letdown. In polyurethane systems, moisture, catalysts, hardeners, and pot-life changes add compatibility risks that are absent from a simple dispersion check.

Mechanism

Solvent polarity and evaporation profile, dispersant adsorption, resin affinity, and water content control wetting and particle interaction. In the cured film, aggregate size, ATO loading, binder index, film thickness, and cure state determine spectral attenuation and any required conductive pathway.

Tradeoff

A solvent blend that stabilizes ATO may not provide the required resin solubility, drying, cure, appearance, or durability. Raising ATO concentration can strengthen NIR attenuation or conductivity while increasing haze, tint, viscosity, settling, and surface-defect risk.

Material Strategy

Define the exact ATO grade and supplied form, solvent package, dispersant, resin, additives, and addition sequence. For polyurethane, include water control, mix ratio, catalyst, induction time, pot life, and cure conditions. If conductivity is outside the scope, compare the distinct absorber route using ATO vs Cs0.33WO3.

  • ATO concentrate into solventborne acrylic: screen solvent shock, resin compatibility, viscosity drift, drying, and adhesion.
  • ATO dispersion in a two-component PU: keep dispersion preparation separate from reactive letdown, then validate pot life and cure completeness.
  • Primer, active layer, and protective topcoat: separate adhesion, NIR control, and weathering functions when one formulation cannot carry all requirements.

Measurement & Validation

Record solvent composition, water content, addition sequence, rheology, particle-size trend, settling, filtration, pot life, drying, and cure. Compare matched panels for spectral transmission or reflection, haze, color, dry-film thickness, gloss or surface defects, adhesion, chemical resistance, and weathering. Add sheet resistance only when electrical performance is specified.

Downloads

Review the ATO Technical Data Sheet, then request application support with the solvent package, resin or PU components, substrate, coating thickness, cure, and optical targets.

Need to apply this boundary to a grade, formulation, test method, or production route? Discuss it with the Aurexene Materials Engineering Team.

Continue the engineering sequence

Next useful paths

A short, deterministic route to the next engineering task, decision comparison, evidence package, or relevant application library.

Decision comparison

ATO vs Cs0.33WO3

Compare the relevant material or architecture tradeoffs before narrowing the route.