DSS-Co.03.02 — Hard-Coat Micro-Mottle (Other Functional Films)

Hard-coat micro-mottle is an appearance change confined to functional hard films (non-pyrolytic low-E alternatives, AR/IR hybrids, solar/anti-glare coatings) presenting as fine, non-directional mottle-a subtle patchwork of reflectance or color within the coated area. The effect is planar within the coating and usually non-tactile. Classification is appearance-only per VIS (method-agnostic). Inspect after Non-Invasive Reveal under VIS lighting/geometry; record surface numbering and worked-surface status.

Face identification is critical. Many functional films are specified on #2 (or #1/#4 by design). Confirm the coated face prior to classification.

• Fine, cloud-like micro-mottle or orange-peel-like optical texture that becomes apparent in oblique sweep or broad specular reflection.
• No coherent directionality (not a rub trail or swirl); no periodic pitch (not roller ghosting).
• Can present lot-wide subtlety (global cast) with localized zones of higher contrast.

Surface-catch class (MSRT)

• SC-0 typical (planar optical variation).
• SC-1 localized only if a minute contact imprint (pad weave/foreign dust) coincides with mottled zone.
• Perform one light, non-marring pass on a small revealed test patch; polymer stylus only on suspected coated faces. MSRT supports classification only; do not abrade the coating.

Visual signature

• Non-directional, fine-scale mottle in reflectance or color; boundaries often soft/feathered.
• No chip-flank sparkle, no discrete grooves, no pits/fused nodules.
• Angle-dependent “flash”-mottle appears/disappears as the observer sweeps.

Viewing / lighting

• Evaluate clean & dry at 12 / 36 / 72 in, normal and oblique sweep (~60°-120°); use broad specular to compare inside vs. outside the mottled zone. Record distances/angles in-frame.

Location / access

• Record pane ID and surface numbering (#1-#4; laminate-internal). If on #2/#3 (IGU interior), it is inaccessible in place → CAT-5 by location (classification remains Co.03.02).

Mechanism cue (context)

• Coating process micro-nonuniformity, post-coat handling/stacking pressure optics, or localized over-cleaning with incompatible media altering the thin-film interference response.

Assign CAT by visibility at acceptance geometry and MSRT.

• CAT-1 (Benign / non-relief): Very faint mottle legible mainly at oblique/raking; SC-0. Indicative relief: 0-10 μm (optical only).
• CAT-2 (Light): Discernible micro-mottle at standard distance in certain lighting; SC-0 (or SC-1 localized if micro-imprint). Indicative relief: ~10-40 μm (apparent optical).
• CAT-3 (Moderate): Pane-noticeable mottled panel at standard distance, affecting uniformity; SC-0/SC-1. Indicative relief: ~40-120 μm (apparent optical).
• Reclassify when: Parallel periodic bands → Co.02.01 Roller pickup; wipe-arc-linked → Co.02.02 Rub/Scuff (pyrolytic) or Co.03.01 AR bloom; linear grooves with chip flanks → M.01 Scoring; rings/runs → Ch.01/Ch.03 chemistry; peppered fusing → Th.01.02 Hot particle.
• CAT-5 (by condition/location): Between-pane/inaccessible or coating-side constraints preclude compliant presentation → CAT-5.

CAT is appearance-based; acceptance is separate under VIS-A at 12/36/72 in. Do not abrade coated faces to “force” a response.

• vs. AR bloom/scuff (Co.03.01): AR bloom often shows distinct reflectivity increase with contact context; Co.03.02 is a fine, non-directional mottle that may be process-intrinsic.
• vs. Pyrolytic rub/scuff (Co.02.02): Pyrolytic rubs are localized wipe/contact panels; Co.03.02 lacks wipe geometry and can appear lot-distributed.
• vs. Mineral/chemical films (Ch family): Chemistry shows rings/runs and may yield SC-1/2; Co.03.02 is planar, ringless, typically SC-0.
• vs. Abrasion fields (M.02): Abrasion presents directional texture with consistent SC-1 along paths; Co.03.02 lacks coherent directionality.

• Photo set (VIS): 12 / 36 / 72 in, normal + oblique; raking macros across mottle boundary; broad specular comparison (inside vs. outside zone). Record distance/angle in-frame.
• Face ID + MSRT. Confirm functional coated face; MSRT (polymer stylus only) on a revealed patch to record SC-class (SC-0 typical; SC-1 localized if present).
• Context notes. Lot repetition (intrinsic) vs. isolated (handling/cleaning); cleaners/media used; storage/stacking history.
• Forms: Pane ID; product family & surface numbering; worked surface Y/N; functional coating present on worked surface? (Y/N/Unknown); reveal status; lighting/time; geometry checklist; photos attached.
• Acceptance split: Post-restoration acceptance per VIS-A §6; classification ≠ acceptance. Coated-face appearance rules apply per VIS §6.2.e when the worked surface is the functional coating.

• Co.03.02 Hard-Coat Micro-Mottle - Fine, non-directional mottle/optical texture on surface #___ (functional coated face confirmed); MSRT (polymer): SC-0 [SC-1 localized if micro-imprint]; visible at [12/36/72 in] under VIS geometry. Morphology: planar thin-film nonuniformity, soft boundaries, no chip-flank grooves, no pits. Classification: CAT-[1/2/3] by visibility; reclassify per notes if roller-pitch, contact rub, mechanical scoring, chemical, or hot-particle indicators are present; CAT-5 if between-pane or coating-side constraints preclude in-place work. Forms + photo set attached; acceptance per VIS-A §6.