D545 vs D547 vs D548 is a comparison of three silicone wetting routes, not a universal winner table. Their published system scope, dosage and supplier scores differ. Choose the real coating defect and vehicle first, then compare candidates at controlled active levels while watching foam, craters, adhesion, recoat and storage.
Waterborne coating route with narrow published scope.
Broad-system route with stronger qualitative foam relevance.
Broad water/solvent wetting route and wider published dose.
Read active substance and content correctly
De D545 page states “active substance 100%” and separately reports “content ≥92%” after a 105°C, three-hour test. Its note attributes the difference to synthesis-related excess low-molecular-weight polyethers counted as volatile. That wording does not justify calling the remainder solvent. Use the supplier’s exact terms and request the current TDS/COA when normalizing trials.
Compare published system and dose evidence
| Rang | Published system scope | Recommended addition | Relevant handling note |
|---|---|---|---|
| AGESIN® WD-D545 | Waterborne wood, industrial and plastic paint | 0.1–0.5% of total formulation | May freeze at low temperature; page says transparency and flow restore after heating |
| AGESIN® WD-D547 | Waterborne, solvent, solvent-free and UV | 0.1–0.5% of total formulation | Broad-system wetting/spreading with qualitative leveling, recoat and defoaming descriptions |
| AGESIN® WD-D548 | Waterborne and solvent systems | 0.1–1.0% of total formulation | May freeze at low temperature; page says heating or solvent dilution restores use |
Treat supplier scores as qualitative
The pages display 0–5 recommendation scores rather than a published standardized head-to-head laboratory study. D545 shows transparency 4, defoaming 0, dynamic surface tension 4, static surface tension 3 and slip 0. D547 shows 1, 3, 3, 4 and 0. D548 shows 4, 0, 5, 4 and 0. These help form hypotheses; they are not statistical proof that one grade will win in a customer formulation.
Use the score pattern to frame experiments
| Question | Possible first candidate | Why it is only a hypothesis | Required counter-check |
|---|---|---|---|
| Waterborne coating needs transparency | D545 or D548 | Both show supplier transparency score 4 | Haze, gloss, compatibility and storage in the actual binder |
| Dynamic wetting at application speed | D548 | Supplier dynamic score is 5 | Production-speed wetting, craters and air |
| Wetting plus qualitative foam relevance | D547 | Only D547 shows defoaming score 3 | Foam decay, density, crater and gloss against a dedicated control |
| Narrow waterborne paint scope | D545 | Its listed applications fit this boundary | Substrate, binder and recoat validation |
Keep the D545 water datum in context
The D545 page reports a surface tension of 20.5 mN/m at 0.2% in water. This is a water test, not proof of coating wetting, adhesion, foam behavior or long-term stability. Pigments, resin, neutralizer, co-solvent and other surfactants can change the result. Do not rank final coatings from that single value.
Screen by system before dosage
D545 has the narrowest published application scope and should not be projected into solvent-free or UV systems without new supplier evidence. D547 covers the broadest listed system set. D548 covers waterborne and solvent coatings and has the widest recommended range. A broad scope does not guarantee compatibility; it only makes a grade eligible for the next controlled test.
Normalize the trial basis
All three pages state 100% active substance, while D545 also carries the separate content-test wording explained above. Run initial comparisons at the same low as-supplied level where published ranges overlap, then optimize each candidate independently. Record addition stage, mixing shear, temperature and aging. Never compare one at 0.1% and another at 1.0% and call the result a product ranking.
Prepare repeatable coating films
ASTM D823 describes practices for producing films of uniform thickness on test panels. Use identical panels, application settings and film build. Include production-relevant spray, roll or brush trials after drawdown screening because dynamic wetting and air entrainment depend on application energy.
Measure foam without over-interpreting it
ASTM D1173 covers foam tests for surface-active agents. A controlled foam test can compare height and decay, but it may not correlate directly with grinding, pumping or spraying. Pair it with wet-density measurements and cured-film inspection under the real process. D547’s qualitative defoaming score is not a replacement for that evidence.
Check adhesion and recoat
ASTM D3359 provides tape-test methods for coating adhesion. Compare the unchanged control and every additive level after the same cure, then repeat after the intended recoat. Document failure location and substrate. Better wetting can still reduce intercoat adhesion if surface segregation becomes excessive.
Handle freeze recovery as a release gate
D545 and D548 pages both mention low-temperature freezing and recovery. Do not assume a warmed container is automatically equivalent to fresh material. Define a controlled recovery temperature and mixing procedure, then inspect clarity, flow, separation and coating performance. Request current supplier storage instructions before using freeze–thaw exposure as a routine acceptance method.
Decision rules
- Shortlist D545 for its documented waterborne paint scope, not for a universal superiority claim.
- Shortlist D547 when the system is solvent-free or UV, or when qualitative foam relevance merits testing.
- Shortlist D548 for water/solvent wetting studies that need its broader published dosage window.
- Approve no grade until controlled panels pass wetting, air, appearance, adhesion, recoat and storage gates.
Information to send with an inquiry
Provide binder and cure chemistry, water/solvent/UV status, pigment volume, current surfactants and defoamers, substrate, viscosity, application, film build, drying, recoat, storage temperature and defect photographs. Ask for current TDS, SDS, COA limits and recommended incorporation for the chosen grade.
Ask Longchang for a controlled D545, D547 and D548 comparison plan.