Coating additives: choose wetting, leveling and surface feel

• For substrate wetting, inspect retreating edges and crater formation on the actual cleaned substrate; include a freshly prepared untreated control.
• For leveling, compare brush or roller marks at the same wet-film thickness, application speed and drying conditions.
• For slip and handfeel, define whether the target is dry, silky or lubricated; evaluate gloss, blocking and scratch response separately.
• For foam-related defects, measure entrained air and foam decay independently of surface tension or flow.
• For multilayer coatings, include intercoat adhesion after the planned waiting period and any surface-cleaning step.

VN-SI-1069 and VN-SI-1070 both list polyether-modified dimethicone. The public descriptions do not provide a quantified distinction that supports treating one as a faster or stronger version. Compare the current active content and viscosity with matched trial panels. VN-SI-1071 lists a silicone oligomer and belongs on a separate identity-based shortlist.

VN-SI-1025 and VN-SI-1026 are acrylate copolymer solutions. The former emphasizes wetting and leveling; the latter also lists defoaming and foam suppression. VN-SI-1019 is a high-molecular-weight dimethicone dispersion supplied as a paste for scratch and handfeel development. The emulsion grades VN-SI-1057 through VN-SI-1063 address different surface-feel descriptions; compare them in the actual topcoat instead of ranking them by model number.

Use a small controlled matrix: untreated control, current benchmark and each candidate at documented trial levels. Keep mixing sequence and hold time fixed. Examine wetting immediately, film appearance after drying, and surface behavior after conditioning. This separates a genuine additive effect from a change in solvent loss or substrate contamination.

If craters appear only after increasing the additive, investigate compatibility and contamination before adding more wetting agent. If bubbles disappear but pinholes remain, inspect film thickness and drying history. Where slip improves but recoating fails, examine additive migration and the next-layer binder. Record failures as well as the best panel so that production approval has a reproducible boundary.