The useful comparison for 907 vs BMS vs ITX begins with the ink, lamp, and film—not the product name. Pigment absorption, film thickness, oxygen exposure, initiator solubility, lamp irradiance, dose, and spectral output can reverse a laboratory ranking. Start with supplier-supported candidates, then confirm the actual absorption/lamp overlap and run a controlled cure ladder.
CHLUMINIT® 907 is listed for screen, lithographic, and flexographic inks as well as wood coatings. CHLUMINIT® BMS is described as a Norrish Type II benzophenone route used with an amine synergist, including clear and pigmented applications. CHLUMINIT® ITX is listed for screen, lithographic, and flexographic inks and wood coatings. Those are screening boundaries, not a promise of cure in a specific ink.
907 vs BMS vs ITX decision map
| Question to answer first | Candidate route | Evidence required before approval |
|---|---|---|
| Does the existing 907 route fit the ink process and deliver cure through the required film? | CHLUMINIT® 907 | Supplier spectrum, solubility, dose ladder, surface and through-cure |
| Is a Type II benzophenone/amine route appropriate for this clear or pigmented system? | CHLUMINIT® BMS plus a validated amine synergist | Actual lamp overlap, synergist level, odor/migration review, cure data |
| Should an ITX route be screened for the selected ink and lamp? | CHLUMINIT® ITX | Supplier spectrum, complete photoinitiator package, color and extractables review |
| Ürün | Published identification | Published application information | Important limitation |
|---|---|---|---|
| CHLUMINIT® 907 | CAS 71868-10-5; white powder; assay ≥99%; melting point 70–75°C | Screen, lithographic, and flexographic inks; wood coatings | Published transmittance values are not a substitute for an absorption spectrum |
| CHLUMINIT® BMS | CAS 83846-85-9; white crystalline; assay ≥99%; melting point 75–85°C | Norrish Type II; supplier lists 246 and 315 nm absorption maxima and 0.5–5 wt% starting concentration | Requires a validated amine synergist; “LED” wording does not prove fit with a specific wavelength |
| CHLUMINIT® ITX | CAS 5495-84-1; white to light-yellow powder; assay ≥99%; melting point 56–72°C | Screen, lithographic, and flexographic inks; wood coatings | Obtain current spectral and formulation guidance before setting a lamp or package |
Screen 907 against film and color, not a slogan
907 is a valid first candidate when the supplier-listed ink applications match the process. The published page also gives transmittance values at 425 and 500 nm, but those quality-control values do not reveal the wavelength-dependent absorption needed for lamp matching.
Ask for the current absorption data in a relevant solvent or formulation and document solubility, storage stability, yellowing/color shift, surface cure, through-cure, adhesion, and odor. Pigment and filler packages must be part of the trial because they can compete for incident radiation and change cure depth.
Treat BMS as a complete Type II package decision
The BMS page identifies a Norrish Type II benzophenone mechanism and says it is used with amine synergists. Therefore, a BMS trial is not just a one-for-one powder substitution: the identity and level of the synergist, resin functionality, pigment, oxygen exposure, and total initiator package all matter.
The supplier lists 246 and 315 nm absorption maxima and includes LED curing among possible applications. Still, confirm overlap with the actual source. A 365, 385, 395, or 405 nm LED has a different output window, and broad application wording alone cannot establish useful absorption or cure at the line speed.
Use ITX only with current spectral and package guidance
ITX is listed for the same major printing processes as 907, which makes it relevant to a controlled comparison. Its public page does not provide enough spectral or synergist-package detail to set a production recipe. Request the current technical data, confirm the intended formulation role, and test the full package rather than ITX in isolation.
Because the material is described as white to light yellow and has a Gardner color limit, color-sensitive work requires a measured ink-film comparison. Also review odor, extractables, migration, and customer restrictions for the intended packaging or industrial use.
Match the real radiation source
- Record the source. Identify mercury or LED equipment, nominal wavelength, measured irradiance, dose, reflector condition, and working distance.
- Obtain candidate spectra. Use current supplier absorption data in a relevant medium; do not infer it from color or transmittance alone.
- Include the ink optics. Measure or document pigment, optical density, film thickness, substrate reflectance, and any UV absorber.
- Run irradiance and dose ladders. Separate a spectral mismatch from insufficient energy or excessive line speed.
- Check surface and depth. A tack-free surface does not prove conversion at the substrate interface.
Build a controlled photoinitiator trial
Hold resin, monomers, pigment dispersion, viscosity, film weight, substrate, application method, and atmosphere constant. For each supplier-supported route, compare a blank/reference and a compact concentration ladder. Measure tack, rub resistance, solvent resistance where appropriate, adhesion, hardness, flexibility, color, gloss, odor, and depth cure at fixed time points.
ASTM D5402 describes solvent rubs for assessing solvent resistance of organic coatings, while ASTM D3359 describes tape adhesion ratings. Neither method alone measures photochemical conversion. Use an agreed instrumental conversion or extraction method when required, and define film thickness, substrate, conditioning, and acceptance criteria before testing.
Control regulatory and customer-fit risks
For printing inks, especially food-contact packaging, selection must include the intended use, substrate, barrier or set-off scenario, curing conditions, migration risk, and regional/customer requirements. The EuPIA raw-material selection framework explains that raw-material suitability is only one part of manufacturing a compliant ink.
Do not describe a material as food-safe, low-migration, or compliant from its chemical name or assay alone. Obtain current regulatory statements and perform the risk assessment and testing required for the finished printed article.
Common comparison mistakes
Choosing by the darkest or longest claimed wavelength
Cure depends on the integrated overlap between source output, initiator absorption, ink optics, and dose. A single wavelength or peak value does not predict production performance.
Comparing equal weight without package context
BMS is published as a Type II route with an amine synergist. Equal-weight substitution against another product may compare incomplete packages rather than candidate performance.
Approving from surface tack only
Measure adhesion and through-cure at the substrate interface, then repeat after conditioning. Excess surface cure can hide weak depth conversion in pigmented or thicker films.
Frequently asked questions
Is BMS automatically suitable for a 395 or 405 nm LED?
No. The supplier lists LED applications but publishes absorption maxima at 246 and 315 nm. Obtain the full spectrum and verify cure under the actual LED output, dose, film, and pigment package.
Does 907 have low yellowing because its transmittance is high?
That conclusion cannot be made from two transmittance values. Measure initial and aged color in the finished formulation at the intended film thickness and cure.
Can ITX be tested alone?
Use it only according to current supplier formulation guidance. Confirm its intended role and the complete initiator/synergist package before comparing performance.
Request a 907, BMS, or ITX screening plan
Send the resin and monomers, pigment and optical density, ink process, substrate, wet and dry film thickness, lamp type and measured output, line speed, current initiator package, cure failures, and regulatory constraints. Ask Longchang Chemical to shortlist 907, BMS, or ITX for a controlled UV ink trial.