Paper varnish additives should be selected by wetting, leveling or verified process air. CHLUMIAG® 2100 is the substrate-entry route, CHLUMILE® 3432 is the film-leveling route, and CHLUMIAF® 3062 is the defoamer route. Rub, blocking, cure and converting remain separate approval gates.
CHLUMIAG® 3501 leaves the first shortlist because its public page lists overprint varnish and anti-sticking applications but gives no recommended dosage or quantified anti-sticking/handling endpoint. A current TDS is needed before a paper-varnish trial.
Paper-varnish decision map
| Observed condition | First check | Route to screen |
|---|---|---|
| Beading, edge pullback or incomplete cover on paper/ink | Paper coat, ink cure, contamination, surface energy and viscosity | 2100 |
| Substrate wets but orange peel or gloss variation remains | Film weight, rheology, drying/cure and application | 3432 |
| Wet bubbles become craters or pinholes | Track air through mix, pump, anilox/roller and application | 3062 |
| Sheets stick after drying | Cure, residual water/solvent, stack heat, pressure and time | Fix process before anti-stick claim |
| Produk | Published fit | Supplier guidance | Boundary |
|---|---|---|---|
| CHLUMIAG® 2100 | Wetting/spreading for difficult substrates and high-smoothness packaging; UV, solvent and water-based | 0.1–1%; grind, stir or post-add; broad dilution options | Page notes reactivity and tool-contamination risk; adhesion must be measured |
| CHLUMILE® 3432 | Overprint-varnish leveling, wetting and anti-crater route; UV, solvent and water-based | 0.05–1%; any stage; broad dilution options | Not a cure or true defoaming route; avoid additive mixtures |
| CHLUMIAF® 3062 | 100% active silicone defoamer for printing/color systems; UV, solvent and water-based | Printing-ink guidance 0.1–0.5% total | Paper varnish dosage needs supplier confirmation; solvent dilution must be tested |
Characterize paper and printed surface first
Record paper or paperboard grade, coat and calender, porosity/absorbency, moisture, recycled content, surface treatment, printing ink, ink coverage, drying/cure age, powder, fountain residues and contamination. An additive cannot make two materially different sheets behave identically.
Use production sheets with the actual ink underneath. Unprinted white paper can hide wetting and intercoat failures that appear over heavy ink coverage.
Use 2100 for a confirmed wetting problem
2100 supports spreading and wetting on difficult and high-smoothness packaging substrates across UV, solvent and water-based systems. Start low within 0.1–1% after contamination, viscosity and paper variability are controlled.
The page also mentions reactivity and avoiding tool contamination. Obtain current handling guidance and measure wetting, edge hold, gloss, adhesion, rub, block, slip and overprint/foil/glue acceptance. Improved initial contact does not prove long-term adhesion.
Use 3432 for film leveling
3432 is supported for overprint varnishes and can improve smoothness, wetting and crater control at 0.05–1%. It is the clearer route when the sheet already wets but the varnish face remains uneven.
Run it alone before combinations. Check flow, gloss/haze, foam, rub, COF, block, adhesion and downstream converting because excessive surface modification can shift several of these at once.
Use 3062 only for measured air
3062 has direct defoaming and foam-suppression positioning. Diagnose where air enters: mixing, recirculation, pump cavitation, roller/anilox transfer or coating head. Compare wet-film bubbles with cured voids.
The public page gives 0.1–0.5% for printing inks, not a paper-varnish-specific range. Confirm the current TDS and application dosage. If solvent dilution is used, test both dilution stability and retained defoaming performance.
Why 3501 needs more evidence
The 3501 page identifies acrylic-modified silicone oil and lists printing inks, overprint varnishes, release coatings and anti-sticking use. However, it publishes no recommended dosage and no quantified blocking, stack or converting result. That is not enough for a primary recommendation.
Measure rub, cure and blocking separately
ASTM D5264 compares abrasion resistance of printed materials, including printed inks, coatings and packaging substrates, using a Sutherland Rub Tester. ASTM D5181 offers a GA-CAT abrasion comparison for printed matter, varnishes and flat packaging substrates. Neither laboratory method reproduces every shipment or stack condition.
For UV varnish, ASTM D5402 can support a solvent-resistance check, but it does not prove full cure. Report actual cure method, coat weight, conditioning, rub receptor/load/cycles, gloss/color loss, block pressure/temperature/time, COF and converting result.
For blocking, define face-to-face or face-to-back contact, specimen area, stack pressure, temperature, humidity, dwell and separation rating. Warm sheets that pass a room-temperature hand test may still offset, gloss-mark or stick in a production pile. Repeat after the intended conditioning time and after any downstream heat step.
Run a production-representative trial
- Fix paper, ink, varnish batch, viscosity, coat weight and line settings.
- Use blank plus one-additive dosage ladder.
- Condition sheets at controlled temperature and humidity.
- Test face-to-face and face-to-back stacks at realistic heat and pressure.
- Include cutting, creasing, folding, gluing, foil or lamination required downstream.
Keep regulatory claims separate
A general product page does not establish food-contact, low-migration, toy, pharmaceutical or recycling compliance. Define the market, packaging layer, barrier, cure, migration scenario and customer specification, then request current declarations for the exact product and use level.
Request a paper-varnish shortlist
Send the paper/board grade, printed ink and cure age, varnish chemistry/solids, current additives, application and coat weight, drying/UV conditions, observed defects, stack conditions, and wetting, gloss, rub, block, slip, adhesion and converting requirements. Ask Longchang Chemical to compare 2100, 3432 or 3062.