Réponse rapide : Buyers choosing a photoinitiator for photosensitive inks should usually separate three different screening paths before comparing grades: a color-filter or black-pigment ultra-thin-film route, a dark-color long-wave imaging route, and a visible-light or laser-oriented precision imaging route. In Longchang’s current product positioning, Photoinitiateur 1206 deserves early attention when the project is directly about TFT-LCD flat-panel display color filters, photosensitive inks, electronic-material inks, very thin films, or high black-pigment burden. Photoinitiateur 369 moves up when the system is darker, more opaque, or harder to cure through and the team wants supported long-wave response plus imaging relevance. Photoinitiateur 784 becomes more relevant when the project is really about visible-light curing, laser-driven imaging, photosensitive layers, or high-precision information-storage style applications instead of a routine UV ink package.
That is the practical split. Photosensitive inks are usually judged by pattern fidelity, cure completeness, pigment burden, wavelength fit, and whether the formulation still behaves well in thin coated layers or precision-imaging steps. A generic UV-ink answer is often too loose.
Why photosensitive inks need a tighter shortlist than general UV ink packages
Many photosensitive-ink projects are not simply trying to dry a printable layer quickly. They are trying to form a controlled image, patterned coating, or functionally precise cured film under stricter process conditions.
- Thin-film behavior matters: some systems are extremely thin, so initiation efficiency and wavelength fit become more sensitive.
- Pigment burden matters: black or dark-color systems can block light and make through-cure much harder.
- Imaging precision matters: display, photoresist-adjacent, or information-storage routes care about more than cure speed alone.
- Light-source fit matters: some projects remain conventional UV-first, while others move toward visible-light, LED, or even laser-assisted imaging.
That is why a better shortlist starts by deciding whether the project is mainly a display or color-filter route, a dark-color long-wave route, or a visible-light precision-imaging route.
For the broader electronics branch, see Photoinitiator for Electronic Coatings. For pigmented printing systems, see Photoinitiator for UV Screen Ink.
Quick comparison table: 1206 vs 369 vs 784
| Produit | Best first fit | Why buyers shortlist it | When it is not the first option |
|---|---|---|---|
| 1206 | TFT-LCD color filters, photosensitive inks, electronic-material inks, and black-pigment ultra-thin films | Longchang directly lists TFT-LCD flat-panel display color filters, photosensitive inks, and electronic-material inks, with high sensitivity at 365 nm, suitability for colored systems including black pigment, and fit for 1 to 30 μm ultra-thin films | When the project is less about ultra-thin or black-pigment display-style imaging and more about broader long-wave cure depth or visible-light precision routes |
| 369 | Dark-color long-wave imaging, pigmented or deeper-curing photosensitive systems, and imaging applications needing stronger penetration logic | Longchang highlights 350 to 380 nm absorption, strong fit for dark-color systems, photopolymers for imaging applications, and electronics uses such as photoresist and solder mask inks | When the main problem is very thin black-pigment color-filter work or when the process is really visible-light or laser driven rather than conventional UV-first |
| 784 | Visible-light, laser-driven, or high-precision photosensitive imaging and information-storage style systems | Longchang directly positions 784 for photosensitive layers, holographic photography, laser direct imaging, three-dimensional lithography, and curing under UV, visible light, or suitable laser irradiation | When the buyer mainly needs a practical 365 nm color-filter benchmark rather than a more specialized precision-imaging route |
When 1206 is the better fit
1206 deserves the first screen when the project is directly about photosensitive inks for display-style, electronic-material, or high-pigment thin-film work.
- Display relevance is explicit: Longchang directly lists TFT-LCD flat-panel display color filters, photosensitive inks, and electronic material inks.
- 365 nm fit is already supported: the current product page describes high sensitivity to 365 nm wavelength.
- Black-pigment pressure is part of the positioning: Longchang states the grade is suitable for colored systems, including black pigment systems, and can withstand up to 35%wt carbon black pigment.
- Ultra-thin-film logic is clear: Longchang also positions 1206 for 1 to 30 μm curing systems, which makes it especially relevant when buyers are not dealing with a broad thick-film package.
If the project is a display-color-filter style route or a photosensitive ink where black pigment, very thin film build, and 365 nm sensitivity matter early, 1206 is usually the cleanest place to begin.
When 369 is the better fit
369 moves up when the system stops behaving like an easy thin-film benchmark and the real problem becomes dark color, opacity, or longer-wave cure-through.
- Long-wave response is a real differentiator: Longchang highlights 369’s ability to capture 350 to 380 nm long-wave UV.
- Dark-system relevance is direct: the company page explicitly positions 369 for dark color systems and high-opacity curing work.
- Imaging relevance is already supported: the recommended-dosage section includes photopolymers for imaging applications.
- Electronics adjacency helps: Longchang also lists uses in solder mask inks et photoresist, which makes 369 easier to justify when the photosensitive-ink project is close to electronic patterning or protective layers.
If the buyer is fighting pigment burden, deeper cure, or dark-system curing under long-wave UV, 369 often deserves earlier screening than a simpler thin-film benchmark.
When 784 is the better fit
784 belongs in a different decision path because it is more obviously tied to precision imaging, visible-light response, and laser-oriented use cases.
- Precision-imaging relevance is explicit: Longchang directly positions 784 for photosensitive layers, holographic photography, laser direct imaging, and three-dimensional lithography.
- Visible-light flexibility is stronger: the product page says curing can be carried out under ultraviolet light, visible light, or suitable laser irradiation, including examples such as 488 nm et 532 nm.
- Imaging or information-storage positioning is already supported: Longchang frames it as especially suitable for imaging or information-storage photosensitive resins in high-tech, high-value-added fields.
- Dark and thick systems are still relevant: the page also notes fit for thick coatings et high-pigment or dark curing systems, so 784 is not only about optical novelty.
If the real process constraint is visible-light activation, laser-driven image formation, or very high imaging precision, 784 deserves earlier attention than a standard display-ink benchmark.
How buyers should choose before requesting samples
1. Start with the real imaging job
Do not treat display color filters, black-pigment photosensitive inks, and visible-light precision-imaging systems as the same buying problem. They often are not.
2. Keep film build visible early
Ultra-thin-film work points naturally toward 1206. Darker, more opaque, or deeper-curing systems often push 369 higher. Precision-imaging or visible-light routes can move 784 forward.
3. Match the wavelength before debating cost
1206 is already positioned around 365 nm sensitivity, 369 around long-wave UV capture, and 784 around UV plus visible-light or suitable laser response. That light-source fit should be screened before a team over-focuses on single-grade price.
4. Separate benchmark routes from specialty routes
If the team wants a practical first benchmark for display-style or photosensitive-ink work, 1206 often belongs early. If cure-through in darker systems is the real bottleneck, 369 moves up. If the system is really about visible-light precision or laser imaging, 784 becomes a more natural lead candidate.
5. Keep the first sample round tight
A useful first screen is often one display or thin-film benchmark, one dark-system long-wave route, and one visible-light precision route if that path is genuinely under review. That usually gives cleaner signal than comparing too many similar products.
Recommended Longchang product and article paths
- Display color filter or black-pigment thin-film route: Photoinitiateur 1206
- Dark-color long-wave imaging route: Photoinitiateur 369
- Visible-light or laser precision-imaging route: Photoinitiateur 784
- Broader electronics article: Photoinitiator for Electronic Coatings
- PCB-adjacent article: Photoinitiator for PCB Solder Mask
- Broader family guide: How to Choose a Photoinitiator for UV Curing
FAQ
Which photoinitiator is the best starting point for photosensitive inks?
In Longchang’s current product positioning, 1206 is usually the strongest first benchmark when the project is directly about TFT-LCD color filters, photosensitive inks, electronic-material inks, or black-pigment ultra-thin films.
When should I choose 369 instead of 1206?
Choose 369 earlier when the system is darker, more opaque, or harder to cure through and the real challenge is stronger long-wave response and deeper cure rather than very thin-film display-style screening.
When does 784 belong in the shortlist?
784 belongs in the shortlist when the project is closer to visible-light curing, laser direct imaging, holographic or information-storage style photosensitive systems, or other high-precision imaging routes.
Are 1206, 369, and 784 interchangeable in photosensitive inks?
No. They may all enter UV-curing discussions, but Longchang’s supported application paths and wavelength logic are different enough that buyers should shortlist them by imaging task, pigment burden, film build, and light source rather than by name alone.
Need a tighter photosensitive-ink shortlist?
If your formulation is being limited by black pigment, very thin coated films, long-wave cure-through, or visible-light imaging precision, define that bottleneck first and then compare only the most relevant Longchang routes. That usually produces a much cleaner sample plan than treating all photoinitiators as interchangeable.