TiO2 for Industrial Coatings

Industrial coatings protect capital assets — steel structures, bridges, offshore platforms, refineries, machinery, pipelines — from environmental degradation. The TiO2 in these systems must contribute to a finished coating that delivers 10–30 year service life under demanding combinations of UV exposure, salt spray, chemical splash, mechanical abrasion, and thermal cycling.

For TiO2 selection, the dominant requirement is photocatalytic stability — the TiO2 must not catalyze degradation of the polymer binder under UV exposure. This rules out anatase and points strongly to heavy-surface-treated chloride rutile. Beyond that, the choice depends on binder system: epoxy primer + polyurethane top-coat is the typical heavy-industrial stack; polyester is common for less aggressive environments; fluoropolymer is used for premium long-life applications.

SEMITI 706 and SEMITI 826D cover the bulk of industrial coatings demand, with SEMITI 902 acceptable for lower-tier industrial applications where 5-year service is sufficient.

Performance requirements

QUV gloss retention

≥ 70% at 2000 hr QUV-A for tier 1 industrial; ≥ 50% at 1000 hr for tier 2

Salt spray (ASTM B117)

1500 hr no field corrosion (with proper primer), no edge creep > 2 mm

Chemical resistance

MEK rub > 100 double rubs; 10% NaOH spot 24hr no whitening

Adhesion (ISO 2409)

Class 0 cross-hatch on substrate

Acid spot etch

No visible mark after 50 μL 30% H2SO4 / 1hr exposure

Dosage guidance

Industrial coating TiO2 loading is generally lower than architectural — 18–28% in topcoats, often supplemented by extender pigments and matting agents for specific gloss targets. Primer formulations may use less TiO2 (8–12%) plus iron oxide or zinc phosphate for active corrosion protection. For heavy-duty industrial topcoats: - Epoxy / PU 2K topcoat (offshore, refineries): 22–28% TiO2 (SEMITI 706 or 826D) - Acrylic-PU topcoat (general industrial): 20–25% (SEMITI 706 or 902) - Polyester topcoat (light industrial): 18–24% (SEMITI 902)

Dispersion / processing notes

Industrial coatings typically use high-shear dispersion equipment (Cowles disk + ball mill, or modern bead mill) to achieve Hegman 7+. Pre-mix TiO2 with the binder and solvent system without dispersant first to test wet-out, then add 0.5–1.5% dispersant (acrylic block copolymer for solventborne; polyacrylate for waterborne) and mill to specification.

Formulation tips

→Pair durable TiO2 (SEMITI 706, 826D) with HALS + UV absorber package for service life > 10 years

→For coastal / marine applications, add zinc phosphate or aluminum tripolyphosphate primer underneath for active corrosion protection

→Polyester binders work well with SEMITI 902; demanding service (PU, epoxy) justifies SEMITI 706 or 826D premium

→Chemical spill containment coatings (acid-resistant linings): use vinyl ester or novolac epoxy + SEMITI 826D, not standard PU

Common pitfalls

Failure modes we've seen in customer trials — worth checking before scale-up.

×Using anatase or sulfate rutile in outdoor industrial coatings — chalking will appear within 2–3 years

×Skipping the primer step in salt-spray environments — even premium TiO2 in the topcoat can't compensate for poor corrosion protection at the substrate

×Mixing 1K and 2K formulation chemistries without cross-linker — leads to under-cured film that fails accelerated weathering testing

Common questions

Which SEMITI grade for offshore / marine coatings?+

SEMITI 706 in the topcoat, with high-build epoxy primer + zinc-rich primer below. The system needs all three elements to deliver 20+ year service in marine atmosphere. TiO2 alone can't save a poorly-designed primer system.

Is fluoropolymer (PVDF) topcoat necessary for premium service?+

For 20+ year coil-coated cladding, yes. For ground-level industrial structures, properly-formulated acrylic-PU with SEMITI 706 / 826D achieves 15+ years at significantly lower cost.

Recommended SEMITI grades