High-pigment solvent ink dispersants should be selected by pigment, resin and mill-base evidence—not by a generic viscosity claim. CHLUMICRYL® DP-D2641R is the broad high-pigment carbon-black, organic-pigment and matte-powder route. CHLUMICRYL® DP-D265R adds an explicit solvent-ink and thermoplastic-acrylic fit.
DP-D200R leaves the first ink shortlist because its public page emphasizes architectural, industrial and anti-corrosion coatings, does not explicitly list inks, and publishes no recommended dosage. It may be evaluated only after current TDS confirmation.
Dispersant decision map
| Mill-base condition | Evidence gate | First route |
|---|---|---|
| High-pigment carbon black, organic pigment or matte powder | Fineness rate, viscosity, color, foam and storage | DP-D2641R |
| Thermoplastic acrylic ink; blackness or organic color spread is limiting | Resin compatibility, blackness/tint and letdown stability | DP-D265R |
| Low initial viscosity but later flocculation | Heat/storage viscosity, rub-up, color and sediment redispersion | Rebuild dosage ladder and resin compatibility |
| Foam or air changes grind readings | Density and air after identical mixing | Fix process before changing dispersant |
| 제품 | Published fit | Supplier data | Boundary |
|---|---|---|---|
| DP-D2641R | Solvent systems; high-pigment carbon black, organic pigment and matte powder | Polymer block copolymer; DBE; 45% active; no stable foam and storage claims | Confirm resin fit and dosage basis in current TDS |
| DP-D265R | Solvent coatings/inks; organic pigments, high-pigment carbon black, thermoplastic acrylic | Polymer block copolymer; DBE; 45% active; color-spread/blackness claims | Thermoplastic acrylic support is not universal resin compatibility |
| DP-D200R | Solvent architectural, industrial and anti-corrosion coating page | Fatty-acid polyamide polyester solution; DPM; 50% active | No explicit ink application or recommended dosage on the public page |
Lock the mill-base before comparison
Hold pigment lot, moisture, surface treatment, resin solution, solvent blend, solids, pigment-to-binder ratio, temperature, vessel geometry, media, fill, speed, time and sampling. A dispersant trial is uninterpretable if the base composition or energy input changes between candidates.
Record density to expose entrained air. Report viscosity at defined temperature, spindle, speed and time after shear instead of one unqualified value.
Use DP-D2641R for broad high-pigment pressure
DP-D2641R directly addresses high-pigment carbon black, organic pigment and matte powder, with published viscosity-reduction, fineness, foam and storage benefits. Add it to the grind material, mix thoroughly, then add pigment as the page instructs.
The supplier table gives inorganic, organic and carbon-black percentage ranges, but the public page does not clearly identify whether the percentage is on pigment, total formula or another basis. Confirm the current TDS before calculating a plant batch.
Use DP-D265R when resin and color fit align
DP-D265R explicitly covers solvent-based coatings and inks, high color spreading for organic pigments, strong blackness for high-pigment carbon black and thermoplastic acrylic resin. This makes it a focused comparator when those conditions match.
Do not generalize thermoplastic-acrylic compatibility to nitrocellulose, polyurethane, polyamide, vinyl, chlorinated or other ink binders. Run letdown compatibility, haze, gloss, adhesion, solvent release and print tests in the actual resin blend.
Why DP-D200R is not a first ink recommendation
DP-D200R publishes broad dispersion, viscosity, gloss and color benefits, but its application section emphasizes architectural, industrial and anti-corrosion coatings. The page provides no recommended dosage and does not explicitly list printing inks. That evidence is insufficient for a confident high-pigment ink first screen.
Measure grind and rheology correctly
ASTM D1210 uses a Hegman-type gage to judge whether pigment agglomerates in a pigment-vehicle system have been sufficiently broken down. ASTM D2196 characterizes apparent viscosity, shear thinning and thixotropy with a rotational viscometer. Neither result alone proves storage or print performance.
Plot fineness and viscosity versus grind time/energy. Add tint strength or blackness, gloss, transparency/hiding, rub-up, density, foam, heat aging, freeze/low-temperature behavior where relevant, sediment, redispersibility and post-letdown drift.
Validate the finished ink
A mill-base winner can fail after letdown. Apply the ink at controlled viscosity and film weight on the actual substrate using the intended gravure, flexo, screen or other process. Measure print density, tone, trapping, drying, residual solvent, adhesion, block, rub and converting.
Storage approval should include more than a visual sediment check. Measure viscosity and color after defined ambient and elevated-temperature aging, then inspect separation, hard settling, redispersibility and rub-up response. Recheck after the aged mill base is let down, because resin or solvent added later can expose flocculation that was hidden in the concentrated grind.
ASTM D5264 provides a controlled Sutherland rub comparison for printed materials, including inks, coatings and packaging substrates. It does not reproduce every shipping temperature, humidity, pressure or contaminant.
Run a disciplined dosage ladder
- Obtain the current TDS and confirm dosage basis.
- Calculate all candidates at equal, documented reference basis.
- Prepare blank plus low, middle and high ladder with identical energy.
- Let down into the same resin/solvent package.
- Age sealed samples and repeat viscosity, color and print tests.
Keep the same sampling time after milling and the same rest time before measurement. High-pigment systems can rebuild structure rapidly; comparing one sample immediately and another after an hour can create a false dispersant ranking.
Request a pigment-and-resin match
Send pigment CI/name, surface treatment, oil absorption, target loading, binder and solvent blend, solids, grind equipment/media, baseline dosage, viscosity curve, fineness, color/blackness, foam, storage failure and final print requirements. Ask Longchang Chemical to compare DP-D2641R and DP-D265R.