3071 vs 3345 vs 3467 is a mechanism-and-evidence comparison. 3071 is a wetting route with an explicit waterborne foam warning and no public active-content value. 3345 is a 100%-active wetting/leveling route. 3467 has multiple dose bases and belongs behind a polyurethane chemistry gate when reaction is claimed.
Substrate wetting with foam risk.
Documented wetting and leveling.
Compatibility or PU modification behind exact chemistry.
Compare current public facts
| Klasse | Published dose/system | Primary question | Critical boundary |
|---|---|---|---|
| 3071 | 0.1–1.0% total; water/solvent/UV | Wetting and spread | No public active value; may stabilize foam in waterborne systems |
| 3345 | 100% active; 0.1–1.0%; water/solvent/UV | Wetting and leveling | Must preserve crater resistance, adhesion and recoat |
| 3467 | 100% active; solvent 0.05–1%; resin modification 0.5–5% resin; waterborne 0.5–5% total | Compatibility or documented PU modification | OH ≤85 mg KOH/g is not an exact stoichiometric value |
Use 3071 for measured wetting
Screen low to high within 0.1–1.0% at fixed substrate, viscosity, film build and application. Measure retraction, craters, edge coverage and adhesion. Record wet density and foam decay because the page warns of foam stabilization. Do not convert dose to active basis without current supplier data.
Use 3345 for controlled leveling
3345 supplies a clear 100%-active basis and 0.1–1.0% range. Compare flow, orange peel, gloss and sag while checking adhesion and recoat. Any-stage addition does not prove grind, letdown and post-addition are equivalent; record stage, predilution and shear.
Do not mix 3467 dose bases
The page gives three different bases for solvent coating, resin modification and waterborne coating. A percentage of resin is not a percentage of total formula. Write every trial in grams, product-as-supplied basis and total or resin denominator so a plant batch can be reproduced.
Require exact PU reaction data
For polyurethane modification, obtain exact batch OH, resin OH, isocyanate equivalent, solids and target NCO/OH. The upper-limit OH value cannot support a precise calculation. Record induction, pot life and cure. Outside a documented PU route, treat 3467 only as an evidence-gated compatibility candidate.
Use a single-variable matrix
| Set | Change | Primary measure | Release gate |
|---|---|---|---|
| A | Control | Wetting, leveling, foam and cure | Adhesion/recoat |
| B–D | 3071 low/mid/high | Entry and coverage | Foam and adhesion |
| E–G | 3345 low/mid/high | Flow and gloss | Sag, crater and recoat |
| H–J | 3467 after data approval | Compatibility/reaction | Pot life, cure and durability |
Prepare uniform films
ASTM D823 describes practices for uniform films. Fix substrate, application, film thickness, temperature, humidity and cure. Production spray or roll trials must follow drawdown screening because dynamic wetting depends on application energy.
Measure gloss without confusing it with cure
ASTM D523 covers specular gloss. Record geometry and film condition. Improved gloss can reflect flow or surface segregation and does not prove cure, adhesion or chemical resistance.
Check adhesion and recoat
ASTM D3359 provides tape adhesion methods. Test the intended coating stack at target and extended recoat intervals, document failure location and follow the project method limits. Surface-active material may improve appearance but weaken the next interface.
Test interactions only after individual routes
Do not combine 3071 and 3345 during the first screen. Their surface effects can overlap, and 3071 can add a foam variable. Establish minimum effective levels separately, then use a small factorial design only if two independent defects remain. Keep an unchanged control through aging.
Repeat the preferred dose at both the lower and upper production viscosity limits. A candidate that works only in one laboratory drawdown may fail when temperature, line speed or application shear moves. Record the process window instead of reporting a single best-looking panel.
Normalize concentration and supplier documents
3071 lacks a public active-content value, while 3345 and 3467 state 100% active. Do not compare the same as-supplied percentage as though the active amounts are known to be equal. Obtain current TDS and COA, record lot number, density and stated active basis, and calculate grams per batch from the approved denominator.
Verify whether product codes, brand family and revision dates on containers match the documents used by the lab. A historical page or alternative-brand table is not a batch specification. Retain reference samples so unexpected foam, haze or cure behavior can be investigated later.
Define defect acceptance before ranking
Set maximum crater count, minimum wetting/coverage, acceptable gloss or leveling, wet-density change, foam-decay time, adhesion rating and recoat result before viewing panels. Predetermined limits prevent an attractive surface from outweighing a cure, foam or interface failure and make plant transfer auditable.
Decision rules
- Select 3071 for wetting with an explicit foam gate.
- Select 3345 for measured wetting/leveling at a known active basis.
- Do not use 3467 generically or mix its three dose bases.
- Require exact OH/NCO data for any reaction claim.
Information to send
Provide binder/crosslinker, water/solvent/UV status, substrate, solids, pH, viscosity, current additives, application, film build, cure, wetting/flow/foam defect, adhesion and recoat needs.