ITX photoinitiator is 2-Isopropylthioxanthone, CAS 5495-84-1. It is a Type II thioxanthone photoinitiator used mainly in UV ink, UV coating, UV adhesive and varnish systems. ITX often works with amine synergists and is commonly tested with 907 or 369 in pigmented UV curing systems. Buyers should check dosage, lamp wavelength, yellowing, odor, migration risk and supplier documents before bulk purchase.
| Buyer Question | Direct Answer |
|---|---|
| What is ITX photoinitiator? | ITX is 2-Isopropylthioxanthone, a thioxanthone photoinitiator used in free-radical UV curing. |
| What is the CAS number of ITX? | The common CAS number is 5495-84-1. Confirm it on COA, SDS, TDS and shipping documents. |
| Is ITX Type I or Type II? | ITX is generally used as a Type II photoinitiator, so it often needs an amine synergist or hydrogen donor. |
| Where is ITX used? | ITX is used in UV ink, UV coating, UV adhesive, varnish, screen ink, offset ink, flexo ink and pigmented curing systems. |
| What dosage should I test? | Many lab trials start around 0.2–2.0%, but the real dosage depends on resin, pigment, film thickness, lamp wavelength and line speed. |
| What is the main technical risk? | Weak curing often comes from poor amine balance, wrong lamp match, high pigment load, poor dissolution or lamp aging. |
| What is the main compliance risk? | Food packaging ink needs migration review, customer approval and regional compliance checks before using ITX. |
| What should buyers request? | Ask for COA, SDS, TDS, assay, batch number, shelf life, storage condition, REACH/RoHS support and sample approval. |
Best Use ITX When vs Recheck ITX When
| Use ITX When | Recheck or Avoid ITX When |
|---|---|
| Your pigmented UV ink needs sensitizing support | Your food packaging project has no migration test |
| Your formula already uses 907 or 369 | Your coating cannot accept yellowing |
| Your system has a suitable amine synergist | Your odor limit is very strict |
| Your mercury UV lamp gives enough usable output | Your LED wavelength has not been tested |
| Your screen ink or offset ink has weak cure | You want to copy another factory’s dosage |
| Your supplier provides COA, SDS and batch traceability | Your supplier only sells by price and cannot support documents |
Why ITX Confuses UV Ink, Coating and Adhesive Buyers
Many buyers ask me, “What is ITX photoinitiator?” I usually answer with another question first: what are you trying to cure?
That question matters. ITX is not a simple yellow powder you buy by CAS number. It is a Type II curing tool. It must match your resin, pigment, lamp, amine package, film thickness and end market.
I have seen buyers add more ITX when black UV ink stays tacky. The real problem was not always ITX. Sometimes the mercury lamp was weak. Sometimes the amine package was wrong. Sometimes the pigment load blocked too much UV light.
This is why I treat ITX as a decision, not just a raw material.
What is ITX Photoinitiator?
ITX photoinitiator is 2-Isopropylthioxanthone, a thioxanthone-based Type II photoinitiator used to start free-radical UV curing in inks, coatings, adhesives and varnishes.
You can verify the chemical identity through the 2-Isopropylthioxanthone chemical record on PubChem and cross-check chemical identity with the NIST Chemistry WebBook. In B2B sourcing, I always ask buyers to match chemical name, CAS number and supplier COA before they compare price.
| ITX Photoinitiator Specification | Buyer Reference |
|---|---|
| Common name | ITX Photoinitiator |
| Chemical name | 2-Isopropylthioxanthone |
| CAS number | 5495-84-1 |
| Photoinitiator family | Thioxanthone |
| Photoinitiator type | Type II |
| Typical appearance | Yellow crystalline powder |
| Common use | UV ink, UV coating, UV adhesive, varnish |
| Key formulation need | Amine synergist or hydrogen donor |
| Main buying risk | Batch consistency, odor, yellowing, migration and documents |
If you need factory testing support, UVIXE supplies ITX Photoinitiator for UV ink, UV coating and UV adhesive manufacturers.
Is ITX a Type I or Type II Photoinitiator?
ITX is generally used as a Type II photoinitiator. This is the first point a technical buyer must understand before comparing ITX with 184, 1173, TPO, 819, 907 or 369.
A Type I photoinitiator absorbs UV light and splits to form radicals. A Type II photoinitiator works through a different route. It absorbs UV energy, reaches an excited state and reacts with an amine or hydrogen donor to generate radicals.
| Factor | Type I Photoinitiator | Type II Photoinitiator |
|---|---|---|
| Radical formation | Cleavage after UV absorption | Hydrogen abstraction or electron transfer |
| Common examples | 184, 1173, TPO, 819, 907, 369 | ITX, DETX, benzophenone systems |
| Amine need | Not always required | Often required |
| Typical strength | Fast cure in clear or low-pigment systems | Sensitizing support in selected systems |
| Common buyer mistake | Comparing only price | Using without correct amine or lamp match |
| Main QC focus | Cure speed, yellowing, depth cure | Amine balance, odor, migration, compatibility |
This is why ITX should not be treated like TPO Photoinitiator. TPO is a Type I phosphine oxide photoinitiator. ITX is a Type II thioxanthone photoinitiator. The curing route is different.
How Does ITX Work with Amine Synergists?
ITX often needs a suitable amine synergist or hydrogen donor to perform well in free-radical UV curing. Without that partner, a buyer may increase ITX dosage and still see weak cure.
After ITX absorbs UV energy, it reaches an excited state. Then it reacts with an amine or hydrogen donor. This reaction helps form active radicals that start polymerization in acrylate systems.
Common amine-related options include:
- EDB-type amine synergists
- EHA-type amine synergists
- Tertiary amines
- Acrylated amines
- Resin systems with suitable hydrogen donor behavior
The Esstech ITX product information also describes ITX as a Type II photoinitiator used with tertiary amines and as a sensitizer in 907 and 369 systems.
In one UV screen ink project, the buyer increased ITX from 0.8% to 1.5%. The tacky surface did not improve. The real issue was weak amine activity and an old mercury lamp.
After we checked lamp output and adjusted the co-initiator package, the formula cured better at a lower ITX level. That is why I do not use ITX dosage as the first repair tool. I check the whole curing window.
ITX Photoinitiator Performance Matrix
| Factor | Why It Changes ITX Performance | Buyer Test |
|---|---|---|
| Pigment load | Pigments block UV penetration and reduce cure depth | Compare clear, white, black and dense colors |
| Film thickness | Thick films need stronger through-cure support | Test surface cure and through-cure separately |
| Lamp wavelength | ITX must absorb enough usable light energy | Use radiometer data and compare mercury vs LED |
| Amine level | Type II systems need a suitable hydrogen donor | Run an amine ladder test |
| Resin type | Oligomer and monomer choice affects cure speed and solubility | Test in the real resin system |
| Oxygen exposure | Oxygen can cause surface tack | Check amine, wax, nitrogen or formula balance |
| Mixing temperature | Poor dissolution causes unstable curing | Check clarity and storage after mixing |
| End market | Packaging, electronics and export markets need different controls | Review SDS, migration and customer standards |
This matrix is more useful than a single dosage number. I use it when helping buyers decide whether ITX, DETX, 907, 369, TPO, TPO-L or 819 should enter the first lab trial.
ITX Photoinitiator for UV Ink
ITX is widely tested in UV ink because pigmented systems often need sensitizing support. It can be used in offset ink, screen ink, flexo ink, inkjet systems and overprint varnish.
| UV Ink Type | Why ITX May Help | Main Risk | First QC Test |
|---|---|---|---|
| UV offset ink | Supports pigmented cure | Odor and migration | Rub resistance and residual odor |
| UV screen ink | Helps thicker ink films | Surface tack and yellowing | Tack-free test and through-cure |
| UV flexo ink | Supports fast-line curing | Low-migration requirement | Line speed and migration review |
| UV black ink | Helps difficult curing packages | Poor UV penetration | Depth cure and adhesion |
| Overprint varnish | Supports surface cure and gloss | Yellowing | Gloss, scratch and odor test |
For black UV ink, I rarely judge ITX alone. I first ask for pigment loading, wet film thickness, lamp power and line speed. Black pigment can absorb or block UV energy, so the wrong cure package can pass a lab drawdown but fail on a fast press.
If your system already uses Photoinitiator 907 or Photoinitiator 369, ITX may be tested as part of a sensitized curing package. But it still needs production validation.
ITX for Screen Printing Ink
ITX is often useful in UV screen ink because screen printing usually creates thicker ink films than offset or flexo printing. Thick film curing needs more than surface dryness. It needs through-cure.
For UV screen ink buyers, I check:
- Ink color and pigment load
- Mesh count and wet film thickness
- Mercury lamp condition
- Amine package
- Substrate adhesion
- Odor after curing
If the ink feels dry on top but fails rub resistance, do not raise ITX first. Check through-cure and lamp output first.
ITX for Offset Ink
ITX can support UV offset ink when pigment load and press speed make curing difficult. It is often tested with other photoinitiators rather than used alone.
For UV offset ink, the main checks are:
- Rub resistance
- Set-off risk
- Odor
- Migration requirement
- Ink-water balance impact
- Batch-to-batch repeatability
For packaging offset ink, I add one more question before price: is this for food-related packaging? If yes, migration review comes before bulk purchase.
ITX for Flexo Ink
ITX may help UV flexo ink curing, but the decision depends heavily on line speed and packaging use. Flexo buyers often run fast production, so small curing weakness becomes a real cost.
I normally ask for:
- Line speed
- Lamp type
- Ink color
- Substrate film type
- Target packaging market
- Low-migration requirement
For food packaging flexo ink, a supplier cannot approve the formula only by sending SDS. Migration testing and customer rules decide the final answer.
ITX Photoinitiator for UV Coating
ITX can support UV coating systems where pigment, film thickness or substrate makes curing harder. Buyers often test it in wood coating, plastic coating, metal coating and protective varnish.
| UV Coating Application | What ITX Can Support | What to Watch |
|---|---|---|
| Wood coating | Cure in stained or pigmented systems | Yellowing and sanding behavior |
| Plastic coating | Surface cure and adhesion support | Substrate compatibility |
| Metal coating | Cure in industrial coating systems | Adhesion and flexibility |
| Clear varnish | Surface cure support | Color shift and odor |
| Pigmented coating | Better response in difficult colors | Through-cure and gloss change |
For clear coatings, I am careful with ITX. Yellowing may not matter in dark inks, but it can become a serious problem in clear varnish or light-color coating.
For a clear plastic coating project, I rejected ITX as the first option because the buyer required low yellowing. We tested Photoinitiator 184, Photoinitiator 1173 and phosphine oxide options first. ITX only entered the trial as a comparison.
ITX Photoinitiator for UV Adhesive
ITX can be used in selected UV adhesive systems, but buyers should test bond strength after aging, not only surface tack.
Adhesive buyers often make one mistake. They check whether the adhesive becomes tack-free, then approve the formula. That is not enough. A UV adhesive must keep bonding performance after heat, humidity, light exposure or aging.
| UV Adhesive Test | Why It Matters |
|---|---|
| Initial tack-free cure | Shows basic curing response |
| Bond strength | Confirms real adhesive performance |
| Aging test | Checks long-term stability |
| Yellowing test | Important for clear bonding |
| Odor check | Important for electronics or consumer-facing products |
| Substrate adhesion | Confirms fit on glass, plastic, film or metal |
ITX may help the curing package, but it is not always the best first choice for clear bonding. The final choice depends on resin, substrate, optical requirement and lamp wavelength.
What is the Recommended ITX Photoinitiator Dosage?
Many ITX lab trials start around 0.2–2.0%, but there is no universal dosage. The final dosage must match the full UV system.
| Application | ITX Screening Range | Co-Initiator Need | Main Risk | QC Test |
|---|---|---|---|---|
| Clear UV coating | 0.2–0.8% | Medium | Yellowing | Color and gloss |
| Pigmented UV ink | 0.5–2.0% | High | Weak through-cure | Rub and solvent resistance |
| Black UV ink | 0.8–2.0% | High | Poor UV penetration | Cure depth |
| UV screen ink | 0.5–2.0% | High | Tacky surface | Tack-free and adhesion |
| UV adhesive | 0.3–1.5% | Medium to high | Weak bond after aging | Peel or shear test |
| Overprint varnish | 0.2–1.0% | Medium | Odor and yellowing | Scratch and odor panel |
Do not copy another factory’s dosage. A formula that works at 80 m/min on one press may fail at 120 m/min on another line. Lamp age, reflector condition, pigment type, film thickness and oxygen exposure all change the result.
ITX with 907 and 369: Why Buyers Purchase Them Together
ITX is often tested with 907 or 369 because it can act as a sensitizer and improve curing response in selected systems. This matters in pigmented UV ink, screen ink, varnish and industrial coating formulas.
| Combination | Why Buyers Test It | Watch Point |
|---|---|---|
| ITX + 907 | Common in pigmented UV systems | Odor, migration, yellowing |
| ITX + 369 | Useful when strong curing support is needed | Cost and compatibility |
| ITX + amine | Core Type II working route | Amine odor and formula balance |
| ITX + DETX | Thioxanthone comparison route | Not always a 1:1 replacement |
| ITX + BAPO / 819 | Tested when deeper cure is needed | Yellowing and cost balance |
| ITX + TPO-L | Sometimes checked for LED-related systems | Wavelength and compatibility |
In buyer trials, I prefer comparing packages instead of comparing single materials. A good test may include ITX + amine, ITX + 907, ITX + 369 and DETX-based options.
If deep cure is the main issue, I may also compare BAPO Photoinitiator 819 or TPO-L Photoinitiator depending on the lamp and formula.
ITX vs DETX vs BAPO vs TPO: Which One Should You Choose?
Choose ITX when your system needs Type II thioxanthone sensitizing support, especially in UV ink and pigmented curing systems. Choose another photoinitiator when your main problem is different.
| Buyer Situation | Better Starting Point | Reason |
|---|---|---|
| Pigmented UV ink needs sensitizing support | ITX or DETX | Thioxanthone sensitizer logic |
| Clear coating needs fast cure | 184, 1173, TPO or 819 | Type I route may fit better |
| Thick film or deep cure is weak | 819 / BAPO | Stronger depth-cure support |
| Current ITX has odor or yellowing issue | DETX or adjusted package | Needs side-by-side testing |
| UV LED system needs review | TPO-L, 819, selected blends | Wavelength match matters |
| Food packaging ink | Low-migration reviewed system | Compliance decides the choice |
For deeper comparison, buyers can read UVIXE’s ITX vs DETX Photoinitiator guide before replacing one thioxanthone with another.
ITX Replacement: When Should Buyers Consider Alternatives?
You should consider an ITX replacement when yellowing, odor, migration concern, LED mismatch or customer approval blocks the formula. Do not replace ITX only because another material is cheaper.
| Reason to Replace ITX | Possible Direction |
|---|---|
| Yellowing in clear coating | 184, 1173, TPO or selected low-yellowing package |
| Strong odor in ink | Adjust amine package or compare DETX |
| Weak deep cure | 819 / BAPO or mixed package |
| LED curing mismatch | TPO-L, 819 or LED-suitable blend |
| Food packaging concern | Low-migration reviewed photoinitiator system |
| Poor solubility | Check resin compatibility or alternative thioxanthone |
A replacement is not a one-line substitution. ITX and DETX are not always 1:1 replacements. TPO and 819 follow different curing logic. The right test compares cure speed, yellowing, odor, adhesion, storage and compliance.
Can ITX Work in UV LED Curing?
ITX may be tested in UV LED systems, but buyers should not assume it will work under every LED wavelength. LED curing depends on wavelength, lamp power, photoinitiator absorption, pigment load and film thickness.
Many UV LED systems run around 365 nm, 385 nm, 395 nm or 405 nm. Mercury lamps give broader spectral output. LED lamps give narrower output, so photoinitiator absorption match becomes more important.
| LED Curing Factor | Why It Matters for ITX |
|---|---|
| LED wavelength | ITX must absorb enough light energy |
| LED intensity | Low intensity can slow radical formation |
| Pigment color | Dark pigments reduce UV penetration |
| Film thickness | Thick films are harder to cure |
| Amine package | Type II route needs proper co-initiator support |
| Line speed | Faster speed gives less exposure time |
Before buying bulk ITX for LED curing, run a real lamp test. Do not rely only on supplier dosage ranges.
ITX Solubility, Compatibility and Storage
ITX performance also depends on dissolution and storage stability. A photoinitiator that does not dissolve well can create inconsistent curing, haze, sediment or batch variation.
| Issue | What Buyers Should Check |
|---|---|
| Slow dissolution | Mixing temperature, resin compatibility and solvent system |
| Crystal formation | Storage stability after 24–72 hours |
| Haze in clear coating | Solubility and purity |
| Sediment in ink | Dispersion process and raw material compatibility |
| Cure variation | Batch consistency and complete mixing |
| Caking during storage | Packaging, humidity control and warehouse condition |
If ITX crystallizes after 24–72 hours in your resin blend, do not approve the formula even if the first drawdown cured well. That early pass may disappear during storage or production.
Store ITX in a sealed container, away from strong light, heat and moisture. Follow the supplier SDS and internal EHS rules.
ITX Photoinitiator Price: What Changes the Real Cost?
ITX photoinitiator price depends on purity, batch consistency, order quantity, packaging, shipping route, document support and supplier reliability. The cheapest quotation can become expensive if it causes reformulation, customs delay or customer complaints.
| Price Factor | Why It Matters |
|---|---|
| Assay and quality control | Affects cure stability |
| Batch consistency | Reduces repeat-order risk |
| Order quantity | Affects unit price and freight cost |
| Packaging | Affects storage and transport safety |
| Sample support | Reduces bulk purchase risk |
| COA / SDS / TDS | Supports customer audit and import |
| REACH / RoHS support | Important for Europe-facing buyers |
| Lead time | Affects factory production planning |
| Shipping route | Affects landed cost and customs timing |
A distributor once asked me only for the lowest ITX price. I asked for the target country and end use first. The product was for packaging ink in Europe, so the real issue was not price. It was document support and migration review.
That is the difference between buying chemical powder and buying a production-ready photoinitiator supply.
ITX Photoinitiator in Food Packaging Ink: What Buyers Must Check
ITX is not automatically suitable for food-contact packaging. Final suitability depends on migration testing, ink formula, substrate, barrier layer, food type, storage condition, customer requirement and local regulation.
EFSA stated in its safety advice on ITX that ITX found in food was undesirable, while the reported levels at that time were not considered a health concern. BfR also discussed ITX migration and safety data in its opinion on ITX in printing inks.
For packaging ink buyers, the practical rule is simple: curing performance is not enough.
| Packaging Question | Buyer Action |
|---|---|
| Is the print used for food packaging? | Confirm food contact status and customer requirement |
| Can ITX migrate into food? | Request migration review and testing |
| Is the ink low migration? | Follow customer and regional requirements |
| Is Europe the target market? | Review EuPIA and local compliance route |
| Is the product for dairy, baby food or beverage? | Use a stricter review process |
| Is there a functional barrier? | Confirm with packaging structure and test data |
The EuPIA printing ink guidance context and CEPE’s Printing Inks – EuPIA information are useful starting points. Still, I recommend a qualified regulatory review because SDS alone cannot approve food-contact use.
Common ITX Formulation Problems I See in Buyer Samples
In real projects, ITX failure is rarely caused by ITX alone. It usually comes from a mismatch in formula or process.
| Symptom | Likely Cause | First Test |
|---|---|---|
| Ink remains tacky | Too little amine or poor lamp match | Add amine screen and check UV output |
| Surface cures but inside stays soft | Film too thick or pigment blocks UV | Reduce film thickness or adjust PI package |
| Yellowing is too strong | ITX level too high or wrong system | Lower ITX and compare DETX / TPO / 819 |
| Strong odor after cure | Amine or residual photoinitiator issue | Check cure completeness and odor panel |
| Batch works once but fails later | Poor raw material consistency | Compare COA, assay and melting point |
| Powder dissolves slowly | Solubility or mixing issue | Check resin compatibility and temperature |
| Storage haze appears | Poor compatibility or crystallization | Run 24–72 hour storage check |
| Customer rejects packaging ink | Migration or odor issue | Review compliance route before scale-up |
This is why I never recommend bulk purchase after one small lab pass. I prefer a three-step approval route: lab drawdown, pilot line and production batch.
TCO: Why Cheap ITX Can Become Expensive
The cheapest ITX quotation is not always the lowest-cost choice. In UV ink and coating factories, a failed batch often costs more than the price gap between two suppliers.
| Cost Item | Low-Control ITX Risk | Controlled Supplier ITX Value |
|---|---|---|
| Raw material price | Looks attractive | May be slightly higher |
| Cure speed | Unstable between batches | More predictable |
| Production line | Slower line speed or rework | Better process control |
| Customer audit | Weak documents | COA, SDS, TDS, batch traceability |
| Export shipment | Customs delay | Correct label and shipping documents |
| Complaint risk | Odor, tack, migration concern | Better pre-shipment review |
| R&D time | Repeated reformulation | Faster approval cycle |
| Real TCO | Can become high | Easier to control |
For buyers in Europe, India, the Middle East and Southeast Asia, I suggest checking more than FOB price. Ask about MOQ, sample lead time, production lead time, packaging, pallet condition, shipping documents, shelf life and technical response.
How to Choose an ITX Photoinitiator Supplier
A good ITX photoinitiator supplier should help you reduce formulation and procurement risk, not only quote a low price.
| Supplier Check | Why It Matters |
|---|---|
| COA for each batch | Confirms test result and traceability |
| SDS and TDS | Supports safe handling and formulation work |
| Stable batch supply | Reduces repeat-order variation |
| Sample support | Allows lab and pilot testing |
| Mixed photoinitiator supply | Helps compare ITX, DETX, 907, 369, TPO, TPO-L, 819, 184 and 1173 |
| Export document support | Reduces customs delay |
| REACH / RoHS support | Helps Europe-facing buyers |
| Technical response | Saves time when curing fails |
| Distributor support | Helps traders serve repeat customers |
If your supplier cannot explain Type II photoinitiator logic, amine support, UV ink curing risk or document requirements, the low price may not help you.
How to Buy ITX Photoinitiator from China
When buying ITX photoinitiator from China, buyers should check both chemical quality and export readiness. This matters for factories, distributors and traders in Europe, the Middle East, India and Southeast Asia.
| Buying Item | What to Confirm |
|---|---|
| Product identity | ITX, 2-Isopropylthioxanthone, CAS 5495-84-1 |
| Technical documents | COA, SDS, TDS, assay, batch number |
| Compliance support | REACH / RoHS if needed |
| Sample order | Amount, lead time, courier route |
| Bulk MOQ | Trial order and repeat order planning |
| Packaging | Carton, drum or export-ready packaging |
| Lead time | Production and dispatch schedule |
| Shipping | Air, sea or courier options |
| Customs documents | Invoice, packing list, label and SDS |
| Repeat supply | Batch stability and long-term availability |
UVIXE supports DETX Photoinitiator, ITX, 907, 369, TPO, TPO-L, 819, 184 and 1173 for buyers who need comparative testing and repeat supply.
ITX Sample Approval Workflow for Factories
Do not move from sample to bulk order too quickly. A good ITX approval workflow reduces technical, compliance and procurement risk.
| Step | What to Do | Why It Matters |
|---|---|---|
| Step 1 | Confirm CAS, COA, SDS and TDS | Prevents wrong-material purchase |
| Step 2 | Run lab drawdown | Checks basic cure response |
| Step 3 | Test amine and PI package | Finds the real curing balance |
| Step 4 | Run pilot line | Confirms lamp, speed and film thickness |
| Step 5 | Check odor, yellowing and adhesion | Prevents customer complaints |
| Step 6 | Review migration if packaging-related | Reduces compliance risk |
| Step 7 | Approve batch and documents | Supports repeat purchase |
This process may look slower at the beginning. In practice, it saves time because it avoids failed production batches.
What to Send UVIXE Before Asking for ITX Price
If you want a useful recommendation, send more than “please quote ITX.” A better inquiry gives the supplier enough information to reduce your testing risk.
| Send This to UVIXE | Why It Helps |
|---|---|
| Application: UV ink, coating, adhesive or varnish | Helps choose ITX, DETX, 907, 369, TPO or 819 |
| Resin type | Affects cure speed and compatibility |
| Pigment color and loading | Affects UV penetration |
| Film thickness | Affects surface cure and through-cure |
| Lamp type and wavelength | Affects photoinitiator choice |
| Line speed | Affects UV exposure time |
| Target country or market | Affects compliance documents |
| Current problem | Helps identify cure failure cause |
| Required documents | Helps prepare COA, SDS, TDS, REACH or RoHS support |
When I receive this information, I can give a more useful answer. Without it, any ITX recommendation is just a guess.
My Practical Recommendation as a UVIXE Supplier
When a buyer asks me whether ITX is the right photoinitiator, I do not answer with “yes” or “no” first. I ask for the application.
For UV ink factories, I check pigment color, printing process, line speed, lamp type and odor requirement. For UV coating factories, I check film thickness, substrate, yellowing tolerance and scratch resistance. For UV adhesive factories, I check bond strength after aging, not only surface tack.
My buying advice is direct:
- Use ITX when you need thioxanthone Type II sensitizing support.
- Do not use ITX alone without checking amine or hydrogen donor logic.
- Do not approve ITX for packaging ink without migration review.
- Do not buy bulk material before sample and pilot testing.
- Do not compare suppliers by price only.
- Compare documents, response speed, export support and batch control.
FAQ About ITX Photoinitiator
What is ITX photoinitiator?
ITX photoinitiator is 2-Isopropylthioxanthone, CAS 5495-84-1. It is a Type II thioxanthone photoinitiator used in UV ink, UV coating, UV adhesive and varnish systems.
What is the CAS number of ITX photoinitiator?
The common CAS number of ITX photoinitiator is 5495-84-1. Buyers should confirm this number on COA, SDS, TDS, product label and customs documents before purchase.
Is ITX a Type II photoinitiator?
Yes. ITX is generally used as a Type II photoinitiator. It often needs an amine synergist or hydrogen donor to form radicals and start UV curing.
Does ITX need an amine synergist?
In many free-radical UV systems, yes. ITX often works with tertiary amines, acrylated amines or other hydrogen donor systems. Without the right co-initiator, curing may remain weak.
What is ITX used for?
ITX is used in UV printing ink, overprint varnish, UV coating, wood coating, plastic coating, metal coating, UV adhesive and selected electronic material systems.
What is the typical ITX dosage?
Many lab tests start around 0.2–2.0%. The final dosage depends on resin, pigment, film thickness, UV lamp, line speed and target curing result.
Can ITX be used with 907?
Yes. ITX is often tested with 907 in pigmented UV ink and coating systems. Buyers should validate cure speed, odor, yellowing and migration risk before bulk production.
Is ITX the same as DETX?
No. ITX and DETX are both thioxanthone-type photoinitiators, but they are not always direct 1:1 replacements. Buyers should compare cure speed, solubility, odor, yellowing and compatibility before switching.
What is the difference between ITX and TPO?
ITX is a Type II thioxanthone photoinitiator. TPO is a Type I phosphine oxide photoinitiator. ITX often needs amine support, while TPO can generate radicals through cleavage.
What is the difference between ITX and 819?
ITX is used mainly as a Type II thioxanthone sensitizer. 819, also called BAPO, is a Type I phosphine oxide photoinitiator often used for stronger depth cure and pigmented systems.
Can ITX work under UV LED?
ITX may work in selected UV LED systems, but performance depends on LED wavelength, intensity, pigment load, film thickness and co-initiator package. Buyers should test under their real lamp.
Does ITX cause yellowing?
ITX can contribute to yellowing in some systems, especially clear or light-color coatings. Buyers should test color change before approving bulk use.
Can ITX be used in black UV ink?
Yes. ITX is often tested in black or dark pigmented UV ink systems. Because black pigment blocks UV penetration, buyers should test through-cure, adhesion and line speed carefully.
Is ITX low migration?
ITX should not be treated as low migration by default. Food packaging ink needs migration review, customer approval and regional compliance checks before use.
Is ITX suitable for food packaging ink?
ITX may appear in food packaging ink discussions, but buyers must review migration risk, customer specifications and regional rules. Do not approve ITX for food packaging only because it cures well.
How should ITX be stored?
Store ITX in a sealed container, away from strong light, heat and moisture. Follow the supplier SDS, warehouse rules and shelf-life guidance.
What purity should I request for ITX?
Buyers should request supplier COA and assay data for each batch. The right purity requirement depends on the application, but batch consistency matters more than a number printed on a quotation.
What documents should I request before buying ITX?
Request COA, SDS, TDS, assay, batch number, shelf life, storage conditions, REACH/RoHS support if needed and shipping documents. Always test a sample before bulk order.
How do I test ITX before bulk purchase?
Start with lab drawdown, then test amine balance, lamp match, odor, yellowing, adhesion and cure depth. After that, run a pilot production batch before approving bulk purchase.
How do I choose an ITX photoinitiator supplier?
Choose a supplier that can provide stable batches, COA, SDS, TDS, sample support, export documents and technical response. Do not choose only by the lowest price.
Final Buying Advice: Do Not Buy ITX by CAS Number Only
ITX photoinitiator is useful, but it is not universal. It works best when the full curing package matches your resin, pigment, lamp wavelength, amine system, film thickness and end-use market.
The real question is not “Is ITX good?” The better question is: “Does ITX fit this UV ink, coating or adhesive formula under real production conditions?”
That is the question I use when helping buyers reduce curing risk.
Ask UVIXE for an ITX Sample and Document Pack
Before you buy ITX in bulk, send UVIXE your application, resin type, pigment system, lamp wavelength, line speed, film thickness and target market.
UVIXE can support ITX, DETX, 907, 369, TPO, TPO-L, 819, 184 and 1173 for comparative testing. For factory testing, we can prepare an ITX sample with COA, SDS and TDS. For distributors, we can discuss repeat batch supply, export packaging, shipping documents and mixed photoinitiator orders.
Start with a sample. Confirm the curing result. Then move to bulk purchase with clearer cost control and lower production risk.