As a new foreign trade service provider driven by both technology transformation and foreign trade services, HiSiaddi has established a "1+2+3+4=1" service system and can supply original factory sources of UV 651 from multiple well-known brands. As a R&D-oriented foreign trade enterprise, HiSiaddi will professionally sort out common difficulties faced by B-end purchasers sourcing UV 651 within China and propose targeted solutions from HiSiaddi.

If you require more professional, in-depth analysis regarding UV 651 purchasing, please contact HiSiaddi customer service.

I. European & American General UV Coating & Wood Furniture Enterprises (Transparent Wood Coatings, Plastic Clear Topcoats, Paper Overprint Varnishes, Indoor Decorative Coatings)

(I) Core Pain Points

Impurities exacerbate coating yellowing, insufficient light transmittance causes foggy films, excessive moisture leads to shrinkage cavity defects, fluctuating activity disrupts curing parameters and residual solvents raise VOC levels.

1. Photosensitive impurities including synthetic by-product methyl benzoin and unreacted intermediates decompose continuously under light and long-term room-temperature storage, causing obvious yellowing of transparent and light-colored wood coatings and plastic films, damaging surface texture and failing to meet long-term appearance requirements for indoor furniture.

2. Residual colored impurities and conjugated organic substances reduce raw material light transmittance, resulting in foggy overall films, insufficient light transmission and loss of mirror finish when used in high-gloss transparent coatings and paper varnishes, lowering coating yield rates.

3. Photoinitiator 651 is hygroscopic; moisture content exceeding 0.1% damages compatibility with UV resins and active monomers, creating shrinkage cavities and pinholes in cured films and drastically increasing rework costs for high-gloss coatings.

4. Deviations in main content and effective active components across batches lead to unstable curing rates, requiring repeated adjustments to UV lamp power and conveyor line speeds on production lines, which easily causes over-curing on surfaces and incomplete deep curing, resulting in substandard coating adhesion and hardness.

5. High levels of low-boiling residual solvents volatilize during coating construction and curing, pushing workshop VOC readings above limits and violating European & American indoor coating environmental and occupational health control standards.

(II) Targeted Solutions

1. Multi-stage vacuum distillation + recrystallization refining processes selectively remove photosensitive impurities, with total organic by-product residues controlled below 0.4% for stable yellowing resistance, preventing severe yellowing of coatings over long-term use.

2. Deep activated carbon decolorization + multi-stage precision filtration maintains high-grade raw material light transmittance with a colorless, crystal-clear appearance, perfectly compatible with high-gloss transparent coating systems.

3. High-vacuum deep dehydration delivers factory moisture ≤0.05%, with fully sealed nitrogen-filled packaging isolating external moisture to fundamentally eliminate film shrinkage cavities and pinholes.

4. Automated closed parameter-locked production stabilizes batch main content ≥99.0% with minimal photoactivity deviation, allowing customers to fix full curing process parameters for consistent continuous mass production.

5. Low-temperature flash evaporation removes residual solvents, with volatile and VOC indicators meeting EU environmental standards for indoor coating operations.

II. European & American Conventional UV Ink & Printing Enterprises (Screen Printing Inks, Paper Printing Inks, General Label Inks, Paper Overprint Varnishes)

(I) Core Pain Points

Small molecule residues cause excessive migration, residual odor impairs finished product experience, incomplete curing leads to overprint sticking, mechanical impurities clog printing equipment and component fluctuations trigger ink stratification and flocculation.

1. Small molecule intermediates and residual solvents readily migrate. When used in indirect food contact labels and packaging printing, migration volumes exceed EU Regulation EU 10/2011 limits, failing food contact compliance audits and restricting access to high-end packaging markets.

2. Residual benzene compounds and low-molecular ethers emit pungent odors that remain on printed products post-curing, contaminating contents in food and daily commodity packaging and endangering safety and consumer experience.

3. Insufficient effective active components lead to incomplete curing under medium-high speed printing conditions, causing overprint adhesion, surface tackiness and poor friction resistance on printed goods with sharply increased reject rates.

4. Trace insoluble mechanical impurities mixed into ink systems easily clog screen printing meshes, ink rollers and print heads, increasing equipment downtime for cleaning and disrupting continuous production rhythms.

5. Fluctuating physical and chemical indicators across batches degrade compatibility with pigments, binders and additives, leading to ink stratification, precipitation and hue shift during storage, destabilizing printing quality.

(II) Targeted Solutions

1. Additional molecular distillation deeply removes migratable small molecules, with migration indicators fully compliant with EU food contact regulations for indirect food contact printed products.

2. Negative-pressure devolatilization and deodorization refining completely eliminate benzene compounds and odor-causing fractions, delivering low-odor finished products with no noticeable residual odor post-curing.

3. Strict control of effective active component ratios guarantees curing efficiency compatible with standard medium-high speed printing lines, thoroughly resolving overprint adhesion and surface tackiness issues.

4. Multi-stage precision filtration removes mechanical impurities to maintain pure ink systems, reduce equipment clogging and ensure efficient printing workflows.

5. Unified component and physical-chemical parameters across batches stabilize compatibility, eliminating ink stratification and flocculation during long-term storage while maintaining consistent printing hues.

III. European & American General UV Adhesive & Daily Commodity Enterprises (Ordinary Plastic Bonding UV Adhesives, Craft Ornament Adhesives, Temporary Positioning Adhesives, DIY Photocurable Products)

(I) Core Pain Points

Residual metal ions impair insulation, moisture creates bubbles in adhesive layers, fluctuating curing shrinkage compromises bonding precision, storage oxidation shortens shelf life and impurities reduce adhesive layer aging resistance.

1. Excess residual sodium, potassium, iron and other metal ions degrade adhesive layer insulation when used for bonding small electronic accessories and insulating ornaments, risking micro-leakage under electric fields and creating safety hazards.

2. Excessive raw material moisture vaporizes under heat during curing, forming micro-bubbles inside adhesive layers that destroy compactness and directly reduce bonding strength and overall stability.

3. Photoactivity differences across batches cause fluctuating curing shrinkage rates, leading to warping, debonding and dimensional deviations when bonding small ornaments and precision plastic parts, undermining assembly and finished product quality.

4. Conventional packaging lacks sufficient light-proof and oxygen-isolating performance, leading to gradual oxidation of raw materials during long-term storage, continuous attenuation of photoactivity, shortened effective service life and hindered inventory turnover.

5. Inert organic impurities accelerate photo-oxidative aging of adhesive layers, causing cracking and debonding of finished products over long-term use and shortening service life.

(II) Targeted Solutions

1. Ion exchange resin + ultrafiltration processes deeply remove metal ions, maintaining ultra-low ion levels to preserve adhesive layer insulation and eliminate electrical safety risks.

2. Extreme vacuum dehydration delivers moisture ≤0.03% paired with sealed moisture-proof packaging for bubble-free compact adhesive layers and stable bonding strength.

3. Standardized production controls curing shrinkage rates with minimal batch deviation, preventing cracking and warping during precision workpiece bonding for consistent assembly accuracy.

4. Light-proof sealed drums filled with nitrogen plus compound long-term antioxidants extend room-temperature shelf life to over 12 months with slow photoactivity attenuation.

5. Deep purification removes inert impurities to boost adhesive layer aging resistance and extend service life of bonded products.

IV. Indian / Southeast Asian General UV Manufacturers (Low-Grade Wood Coatings, Civil Printing Inks, Ordinary UV Adhesives, Daily Decorative Products, Cost-Oriented Mass Procurement)

(I) Core Pain Points

High pricing of high-purity grades squeezes profit margins, industrial crude grades suffer yellowing and poor curing, frequent batch indicator fluctuations for large-tonnage shipments require repeated process adjustments, high-temperature high-humidity storage & transportation degrade product quality and missing compliance documents prevent local registration.

1. High-purity refined photoinitiator 651 carries high procurement costs that compress profit margins for low-grade coatings, civil inks and ordinary adhesives; low-cost industrial crude grades feature low purity and high impurities, delivering slow curing speeds and severe product yellowing that fail to meet local basic usage standards, creating a dilemma between cost and quality.

2. High levels of harmful impurities and residual solvents in crude grades produce coatings and adhesives with poor water resistance and aging resistance, prone to peeling, debonding and discoloration after short-term use, driving high end-product rework rates that raise overall comprehensive usage costs instead of reducing them.

3. Large-tonnage deliveries exhibit significant batch differences in purity, moisture, chroma and activity, requiring repeated adjustments to addition ratios, UV lamp power and production line speeds at manufacturing plants, frequent equipment shutdowns for debugging and drastically reduced capacity utilization.

4. Local ocean shipping and warehousing environments feature high temperatures and humidity; ordinary packaging offers inadequate sealing and moisture resistance, accelerating raw material moisture absorption and oxidation, deepening chroma and attenuating photoactivity to render goods unusable upon arrival with high cargo loss rates.

5. Missing English COAs, MSDS, REACH compliance statements and VOC test reports prevent industrial product registration and routine local market sampling inspections, limiting sales to informal channels and introducing compliance and payment recovery risks.

(II) Targeted Solutions

1. Cost-effective general industrial grade 651 is launched with simplified high-end refining processes including deep rectification and molecular distillation, meeting core indicator requirements for low-grade coatings, inks and adhesives at prices over 25% lower than high-purity refined products to boost profit margins.

2. Basic removal of major yellowing-causing impurities and residual solvents guarantees fundamental curing performance, water resistance and aging resistance to reduce finished product discoloration and debonding issues.

3. Standardized mass production control narrows batch indicator deviations, enabling customers to fix production process parameters long-term, cutting equipment debugging frequency and maximizing production capacity output.

4. Thickened sealed plastic drums with double-layer moisture-proof inner liners and built-in desiccants strengthen moisture and oxidation resistance, preserving stable activity and chroma during ocean transportation and storage.

5. Streamlined English document packages including test reports, MSDS and compliance statements are provided to meet local regulatory registration and routine sampling inspection requirements, supporting expansion into formal supply chains.

V. Overseas Chemical Repackaging & Traders (Regional Distribution, Specification Repackaging, UV Curing Raw Material Circulation)

(I) Core Pain Points

Shoddy supply falsely labeled for purity and activity, liquid material leakage during transit, color degradation and quality downgrade via storage oxidation, incomplete hazardous goods compliance documents and lack of third-party reports leading to loss of high-end customers.

1. Market irregularities exist: some merchants pass low-purity crude grades off as high-purity 651 with falsely labeled main content, light transmittance, anti-yellowing and activity indicators. Downstream coating, ink and adhesive customers experience mass product quality issues triggering high compensation claims and severe damage to channel reputation.

2. Although photoinitiator 651 is described as liquid in this segment, large packaging drums deform and sealing gaskets age and detach during ocean stacking and handling, causing material leakage that contaminates surrounding goods and sparks logistics disputes.

3. Simple packaging lacks light and oxygen isolation, leading to gradual raw material oxidation during cross-border storage and long-distance transportation, deepening chroma and attenuating photoactivity for direct rejection by high-end purchasers and economic losses.

4. Classified as a flammable organic solid, missing English SDS, REACH-SVHC screening, ocean dangerous goods identification certificates and migration test reports block access to formal European & American factories and brand supply chains, limiting sales to low-end markets only.

5. Absence of full third-party test reports and complete batch traceability records prevents passing supplier qualification audits by leading European & American enterprises, forfeiting long-term high-value premium orders.

(II) Targeted Solutions

1. Original factory direct supply of genuine goods with truthful labeling of all physical, chemical and performance parameters; full third-party complete test reports accompany every batch to support re-inspection by any global institution, eliminating adulteration and false labeling risks and preventing after-sales disputes from the source.

2. Thickened solvent-resistant dedicated drums with double sealing lids and aging-resistant fluororubber gaskets undergo leakage pressure testing drum-by-drum before delivery to achieve leakage-free full transit.

3. Uniform light-proof sealed packaging paired with anti-oxidation and oxygen-isolation protection systems inhibit oxidative discoloration and activity attenuation, maintaining stable product grade throughout storage and transportation.

4. One-stop provision of full English compliance documents: SDS, REACH-SVHC reports, ocean dangerous goods identification certificates and food contact migration reports to support customers expanding into high-end European & American circulation channels.

5. Complete batch traceability archives covering full production, quality inspection and warehousing records are established to fully support customer factory audits and supplier qualification reviews, securing long-term high-quality cooperation orders.

For more professional and in-depth analysis on UV 651 purchasing, please contact HiSiaddi customer service.

Lead time

The monthly inventory volume of Photoinitiator 651 is 15 tons, with appropriate adjustments upwards or downwards in response to peak and off-peak seasons.

HiSiaddi safeguards the supply stability of Photoinitiator 651 through the following measures:

1. Supply of one mainstream Photoinitiator 651 model by 3 premium factories

(1) Performance evaluation and screening of Photoinitiator 651 brand factories based on on-time delivery rate, batch pass rate, timeliness of risk alerts, and completeness of documentation to assess their supply stability.

(2) For each mainstream model or major grade of Photoinitiator 651, secure 1 primary high-quality brand manufacturer and 2 backup high-quality manufacturers.

(3) Each factory operates independent production lines in separate production zones to prevent production halts caused by major unforeseen incidents such as environmental production suspensions and power outages.

2. Technological transformation partnerships and long-term sales binding for Photoinitiator 651

Through long-term cooperation with brand manufacturers via technology commercialization and authorized distribution channels, HiSiaddi can effectively strengthen supervision over the production processes of brand manufacturers, optimize full-process traceability management, improve batch stability control, and further reinforce real-time monitoring of the supply stability of Photoinitiator 651 products.

Long-term Annual Framework Supply Guarantee Agreement. HiSiaddi signs 12-month long-term agreements with leading manufacturers. The agreements specify the minimum guaranteed supply volume, maximum price hike range, and priority production scheduling rights during peak seasons. It is stipulated that manufacturers shall issue a 30-day prior written notice if production is suspended due to environmental rectification or equipment maintenance, and backup manufacturers will be activated to replenish goods accordingly.

3. 4 warehouses and 15 peak & off-peak demand forecasting

We have 4 warehouses, which are jointly operated and managed with suppliers to store hot-selling products.The four warehouses are located at Qingdao Port in North China, Ningbo Port in East China, Shenzhen Port in South China, and Zhengzhou, China’s inland logistics hub. This setup guarantees sufficient supply and timely shipment of Photoinitiator 651 during peak seasons.

HiSiaddi issues a rolling demand forecast covering the subsequent three months on the 25th of each month, allowing manufacturers to reserve production capacity in accordance with the forecast. Any new urgent orders from overseas clients will be prioritized to draw on inventories or production capacity from backup manufacturers.

4. Multi-channel logistics to resolve vessel congestion and inspection delays for Photoinitiator 651 sea and land shipments

Unstable logistics for Photoinitiator 651 will extend delivery lead times. HiSiaddi has established alternative arrangements covering multiple freight forwarders, ports and transportation solutions:

(1) Binding of multiple professional chemical freight forwarders for Photoinitiator 651

Each product is assigned 2 to 3 freight forwarders with hazardous chemical/food transport qualifications affiliated with different shipping lines. Alternative sailing schedules can be switched to immediately in case of space shortages or customs inspections on a single shipping route.

(2) Backup transportation solutions for Photoinitiator 651

Ocean freight serves as the standard mode; air freight and rail freight are reserved as alternatives for urgent orders. Long-term agreements for temperature-controlled containers are signed for temperature-sensitive and perishable food additives to secure shipping space.

(3) Visual tracking and digital early warning for Photoinitiator 651

Freight forwarders synchronize daily updates on container loading, customs declaration, vessel loading and port arrival milestones. If customs inspection occurs, replenishment from backup inventory will be initiated immediately to shorten client waiting periods.

Full-chain digital early warning automatically monitors four categories of risks:

• Factory side: Expiring supplier environmental assessment certificates, renewal of production permits, scheduled major equipment overhauls, and notifications of price hikes for upstream raw materials;

• Inventory side: Inventory falling below safety thresholds, excessive inventory age, and batches failing quality inspection;

• Logistics side: Shipping line space shortages, strikes at destination ports, and updates to customs policies;

• Overseas side: Revisions to additive regulations and adjustments to import restriction lists in target countries.

Early warning notifications are automatically pushed to procurement and business leads, allowing backup suppliers or inventory contingency plans to be activated in advance.

UV 651: What Qualification Certifications Have Major Chinese Brands Obtained? What Is Their Market Feedback?

As a new foreign trade service provider driven by dual engines of technology transformation and foreign trade export, HiSiaddi has built a "1+2+3+4=1" service system and can supply UV 651 directly from multiple well-known original manufacturers.

Possessing R&D capabilities, HiSiaddi differs from single-brand factories that only promote their own products. We objectively analyze multiple competitive Chinese export brands of UV 651 and share their qualification certifications and market feedback to help buyers select products efficiently and reliably.

For more authentic, objective information on multiple well-known Chinese brands of UV 651, please contact HiSiaddi customer service.

I. Qiangli New Materials (Jiangsu): Global Leader in Electronic-Grade UV 651

Main Grades

· Standard Grade: PI-651 (Purity ≥99.5%, APHA ≤50)

· Low-Migration Grade: PI-651-L (Migration ≤0.08mg/dm², food-contact compliant)

· LED-Specific Grade: PI-651-LED (Absorption band 380–420nm, compatible with 395nm LED light sources)

Core Market Feedback

· Electronics Industry: Core supplier to global PCB photoresist giants (Tokyo Ohka Kogyo, JSR, Sumitomo Chemical). Clients praise its "batch consistency deviation ≤0.2%, metal ions ≤3ppm, curing efficiency 10% higher than imported equivalents", capturing over 30% global market share in 2025.

· Southeast Asia & South America: Export growth exceeding 20% for three consecutive years. Clients note "25% better cost-performance than BASF with lead times of 2–3 weeks vs. 4–6 weeks for international giants".

· LED Curing Scenarios: Manufacturers of consumer electronic casings and flexible printing plates recognize its "superior LED compatibility with incomplete drying rates below 1%".

Authoritative Accreditations

✅ EU REACH Registration, RoHS, FDA Food Contact Certification ✅ ISO 9001/14001, Electronic-Grade High-Purity Production Qualification ✅ "Premium UV Curing Material Supplier" awarded by China Chemical Industry Association ✅ Compliant with Japan JIS K 6833 and Germany DIN 50017 Standards

II. Jiu Ri New Materials (Tianjin): Benchmark for Optical Fiber & High-End Coating-Grade UV 651, Widely Recognized in European & American Markets

Main Grades

· General Grade: JR-651 (Purity ≥99.5%, excellent thermal stability)

· Optical Fiber Special Grade: JR-651-F (Low volatility, high transparency for optical fiber coatings)

· Anti-Yellowing Grade: JR-651-W (Yellowing resistance grade ≥4, for high-end wood coatings)

Core Market Feedback

· European & American High-End Markets: Operates European offices and Japanese subsidiaries. Clients confirm its "quality matches BASF Irgacure 651 at 15%-20% lower prices", with exports accounting for 34.92% of total revenue in 2025.

· Optical Fiber Coatings: Captures 60%-70% global market share with deep partnerships with Feikai Materials and Covestro. Clients report "fast curing speed, strong adhesion and superior anti-aging performance".

· Wood & Plastic Coatings: Middle Eastern and North American clients praise its "anti-yellowing properties, high gloss and consistent batch performance".

Authoritative Accreditations

✅ REACH Registration, FDA, EU Food Contact Standard (EU 10/2011) ✅ ISO 9001/14001, Japan Ministry of Health, Labour and Welfare Certification ✅ Recommended Supplier by Optical Fiber Communication Society (OFS) ✅ US EPA & EU CE Certification

III. Yangfan New Materials (Zhejiang): Leader in General & Low-Migration UV 651

· Standard General Grade: YF-651 (Purity ≥99.0%, superior cost-performance)

· Low-Migration Environmental Grade: YF-651-E (Migration ≤0.1mg/dm², REACH compliant)

· High-Activity Grade: YF-651-H (15% higher initiation efficiency for high-solids systems)

Core Market Feedback

· Southeast Asia & Middle East: Exports account for over 60% of total sales. Clients comment on its "affordable pricing, stable quality and fast service response", with sales up 18% year-on-year in 2025.

· Inks & Adhesives: Flagship product at European Coatings Show (ECS). Clients report "excellent monomer compatibility, complete curing and low odor".

· Environmental Substitution: Favored as a replacement for high-migration traditional photoinitiators, rated a "preferred REACH-compliant environmental product".

Authoritative Accreditations

✅ REACH Registration, RoHS, EU ECO Environmental Label ✅ ISO 9001/14001, Provincial High-Tech Enterprise Certification ✅ "Innovative Environmental Material Award" at 2025 European Coatings Show ✅ Passed SGS (Switzerland) and TUV (Germany) Testing

IV. Fullaid Chemical (Hubei): Expert in High-Purity & Customized UV 651, Stable Reputation in Mid-to-High-End Markets

Main Grades

· High-Purity Grade: FLD-651-HP (Purity ≥99.8%, electronic/medical grade)

· Standard Grade: FLD-651 (Purity ≥99.5%, industrial general use)

· Blending-Specific Grade: FLD-651-M (Boosts efficiency in LED systems blended with TPO/184)

Core Market Feedback

· Medical & Food Packaging: European and American clients recognize its "high purity, low residuals and strong biosafety" as a viable import substitute.

· High-End Inks: Korean and Japanese printing manufacturers praise its "light color, high transparency and sharp printing dots".

· Customization Services: Flexible adjustments to purity, chroma and migration indicators per client demand; clients highlight "high flexibility and fast R&D response".

Authoritative Accreditations

✅ REACH Registration, FDA, ISO 10993 Medical Biocompatibility Certification ✅ ISO 9001/14001, Certification by China Chamber of Commerce for Import and Export of Light Industrial Products and Arts-Crafts ✅ Compliant with EU EN 71-3 (Toy Safety) and US FDA 21 CFR 175.300

V. Sinocure (Shandong): Export-Oriented UV 651 Brand, Global Cost-Performance Choice

Main Grades

· General Export Grade: Sinocure BDK/651 (Purity ≥99.5%, APHA ≤50)

· Economy Grade: Sinocure 651-Lite (Purity ≥99.0%, prominent price advantage)

· High-Transparency Grade: Sinocure 651-Clear (Light transmittance ≥96%, for optical films)

Core Market Feedback

· Global Distribution Market: Coverage across Europe, South America and Africa. Clients comment on its "stable quality, strong price competitiveness and robust bulk delivery capacity".

· DIY & Small-Scale Curing Enterprises: Southeast Asian and Middle Eastern buyers note "ultra-high cost-performance, simple operation and consistent curing results".

· Blending System Compatibility: Excellent miscibility with 184, TPO, ITX and other initiators, rated a "formula-friendly photoinitiator".

Authoritative Accreditations

✅ REACH Registration, RoHS, EU CE Certification ✅ ISO 9001/14001, Class A Export Enterprise recognized by China Customs ✅ Passed SGS (Switzerland) and EU REACH SVHC Testing ✅ Member of RadTech International North America

VI. Summary: Core Advantages & Selection Recommendations for Five Major Brands

Core Advantage Comparison

· Qiangli New Materials: Electronic-grade quality, superior LED compatibility, robust technical service; ideal for PCB, semiconductors and high-end electronics

· Jiu Ri New Materials: Benchmark for optical fiber and high-end coatings, comprehensive European & American certifications; suitable for optical fiber and high-end wood coatings, food packaging

· Yangfan New Materials: Top cost-performance, broad emerging market coverage, full environmental compliance; fit for inks, adhesives and Southeast Asian markets

· Fullaid Chemical: High-purity medical-grade products, powerful customization capabilities; perfect for medical consumables and food contact applications requiring ultra-high purity

· Sinocure: Export-focused, ultimate cost-performance, reliable global delivery; best for general industrial applications, distributors and small & medium clients

For more authentic, objective information on multiple well-known Chinese brands of UV 651, please contact HiSiaddi customer service.

UV 651: Production Processes, Supply Stability & Key Indicators of Five Major Chinese Brands

As a new foreign trade service provider driven by dual engines of technology transformation and foreign trade export, HiSiaddi has built a "1+2+3+4=1" service system and can supply UV 651 directly from multiple well-known original manufacturers.

Possessing R&D capabilities, HiSiaddi differs from single-brand factories that only promote their own products. We objectively analyze multiple competitive Chinese export brands of UV 651 and share their production processes, supply stability, key indicators and corresponding impacts on buyers to help buyers select products efficiently and reliably.

For more authentic, objective information on multiple well-known Chinese brands of UV 651, please contact HiSiaddi customer service.

I. Qiangli New Materials (Jiangsu): Electronic-Grade Closed-Loop Process + Ultra-Stable Supply, Leader in High-End Electronic Applications

(I) Production Process: Full Industrial Closed Loop + Low-Temperature Catalytic Crystallization for High Purity & Low Consumption

· Core Route: Self-developed integrated closed-loop process from benzoin → benzil → UV 651 with self-synthesis of key upstream raw material benzoin to eliminate impurity introduction from outsourced materials.

· Key Technology: Low-temperature catalytic crystallization paired with continuous-flow microreactors. Reaction temperature controlled at 10–25°C with precise temperature regulation and millisecond-scale mixing, delivering main reaction selectivity of 96.5% and by-product generation below 3%.

· Refining Flow: Methanol dissolution → activated carbon decolorization (2.5h) → microfiltration → low-temperature crystallization (15–20°C) → centrifugal water washing → vacuum drying. Purity stabilized above 99.5% with APHA chroma ≤50.

· Environmental Advantages: 38% lower steam consumption, 45% reduced wastewater generation, VOC emissions limited to 3.1kg/ton, fully compliant with EU REACH and China’s environmental standards.

(II) Supply Stability: 12,000-Ton Capacity + Dual-Base Redundancy, 2–3 Week Lead Times

· Capacity Scale: Dedicated annual capacity of 12,000 tons, with 40% allocated to UV 651 production (4,800 tons/year), the world’s largest electronic-grade UV 651 production capacity.

· Base Layout: Dual redundant production sites (Changzhou Headquarters + Nantong Branch). One base can fully offset production halts during maintenance of the other, eliminating supply interruption risks.

· Inventory Guarantee: Permanent safety stock of 1,000 tons covering standard, low-migration and LED-specific grades, sufficient to fulfill 3 months of global orders.

· Delivery Capacity: Shipment within 7 days for standard orders, 48-hour response for urgent orders; 2–3 week lead times for Europe/America/Southeast Asia, 50% shorter than international giants (4–6 weeks).

(III) Key Indicators: Stringent Electronic-Grade Control, Batch Consistency Deviation ≤0.2%

· Purity: ≥99.5% (electronic grade), ≥99.8% (custom high-purity grade)

· Metal Ions: ≤3ppm (Na/K/Ca/Fe), meeting PCB photoresist and semiconductor packaging requirements

· Chroma (APHA): ≤50, pure white crystal without yellow tint, compatible with optical films and high-end inks

· Migration: ≤0.08mg/dm² (PI-651-L low-migration grade), compliant with FDA food contact standards

· Absorption Band: 250–350nm (standard grade), 380–420nm (PI-651-LED LED-specific grade)

· Batch Consistency: Purity fluctuation ≤0.2%, melting point deviation ≤0.5°C, curing efficiency difference ≤1%

(IV) Impacts on Downstream Buyers: Perfect Match for High-End Electronic Rigid Demand, Near-Zero Quality Risks

· Positive Impacts: Buyers of PCB photoresists, semiconductor packaging and optical films can directly replace BASF Irgacure 651 with matching performance at 15%-20% lower prices. Excellent batch consistency eliminates mass rework risks, while low-migration and LED-specific grades enable market access to high-end sectors.

· Potential Drawbacks: High-end grades carry an 8%-12% price premium over generic domestic brands, requiring cost-sensitive buyers to balance cost-performance.

II. Jiu Ri New Materials (Tianjin): Full Industrial Chain Synergy + Continuous Production, Benchmark for European & American High-End Markets

(I) Production Process: Self-Sufficient Raw Materials + Continuous Synthesis for Superior Thermal Stability

· Core Route: Full industrial chain from gallnut extract → pyrogallic acid → benzoin → UV 651, controlling globally scarce natural raw materials with raw material purity ≥99.9%.

· Key Technology: Continuous reaction kettles paired with gradient temperature-rising ketalization, reaction temperature 25–60°C, reaction duration 8–10h, conversion rate above 95%.

· Refining Flow: Recrystallization (methanol/ethanol mixed solvent) → activated carbon decolorization → precision filtration → vacuum drying, purity ≥99.5% with outstanding thermal stability (decomposition temperature ≥120°C).

· Process Characteristics: Low volatility, high transparency, anti-yellowing grade ≥4 (JR-651-W), ideal for high-end wood coatings and food packaging.

(II) Supply Stability: 8,000-Ton Capacity + Global Warehouse Network, Priority Delivery for European & American Orders

· Capacity Scale: Total annual capacity of 8,000 tons, 3,000 tons allocated to UV 651 production, with optical fiber special grade (JR-651-F) accounting for 50%.

· Base Layout: Tianjin Headquarters + Hunan Zhangjiajie Raw Material Base, integrated raw material-production layout to mitigate raw material price volatility risks.

· Inventory Guarantee: Permanent stock of 500 tons at Tianjin, 300 tons at German European warehouse and 200 tons at Singapore Southeast Asian warehouse, enabling global restocking within 48 hours.

· Delivery Capacity: 2-week delivery for European & American orders, 1-week for Asia-Pacific orders; long-term agreement clients receive priority scheduling with 70% capacity reservation rate.

(III) Key Indicators: Optical Fiber & Food-Grade Standards, Dual Advantages of Anti-Yellowing & High Transparency

· Purity: ≥99.5% (general grade), ≥99.7% (JR-651-F optical fiber special grade)

· Melting Point: 64–67°C with deviation ≤0.3°C, excellent thermal stability

· Light Transmittance (10% toluene solution): ≥95% at 425nm, ≥96% at 450nm, ≥98% at 500nm, optical-grade high transparency

· Volatile Content: ≤0.2%, low odor, compatible with food-contact materials

· Anti-Yellowing Grade: ≥4 (JR-651-W), no yellow discoloration during long-term service

(IV) Impacts on Downstream Buyers: Top Choice for Optical Fiber & High-End Coatings, Hassle-Free European & American Compliance

· Positive Impacts: Buyers of optical fiber coatings, high-end wood coatings and food packaging effortlessly meet EU 10/2011 and FDA standards. High transparency and anti-yellowing properties enhance end-product appearance, while the global warehouse network cuts lead times and logistics costs.

· Potential Drawbacks: Optical fiber special grade carries a 10%-15% price premium, creating high procurement thresholds for small & medium buyers.

III. Yangfan New Materials (Zhejiang): Efficient General-Grade Process + Large-Scale Production, Cost-Performance Champion for Emerging Markets

(I) Production Process: Optimized Batch Kettle + Low-Cost Refining to Guarantee Cost-Performance

· Core Route: Benzoin + dimethyl sulfate → ketalization → refining via traditional batch kettles, with optimized parameters to boost efficiency and reduce costs.

· Key Technology: Reaction temperature 15–30°C, reaction duration 10–12h, dioxane solvent recycling (recovery rate ≥85%) to cut raw material consumption.

· Refining Flow: Crude product alkali fusion → water washing → methanol recrystallization → centrifugal drying, purity ≥99.0% (YF-651 general grade), ≥99.5% (YF-651-E environmental grade).

· Process Characteristics: Large-scale mass production with controllable costs, prices 30% lower than imported equivalents, suitable for general ink and adhesive scenarios.

(II) Supply Stability: 10,000-Ton Capacity + Flexible Scheduling, Rapid Response for Emerging Markets

· Capacity Scale: Total annual capacity of 10,000 tons, 5,000 tons allocated to UV 651 production, with general grade accounting for 70%, ranking as the world’s largest general-grade UV 651 supplier.

· Base Layout: Single large-scale production base in Quzhou, Zhejiang, with flexible scheduling enabling rapid switching between general and environmental grades.

· Inventory Guarantee: Permanent stock of 800 tons general grade + 200 tons environmental grade, same-day shipment for Southeast Asian and Middle Eastern orders.

· Delivery Capacity: 7-day lead time for Asia-Pacific, 10 days for Middle East, 14 days for South America; flexible small-batch orders starting at 100kg for small & medium buyers.

(III) Key Indicators: Industrial General Standards, Prioritizing Cost-Performance & Compliance

· Purity: ≥99.0% (YF-651), ≥99.5% (YF-651-E)

· Chroma (APHA): ≤100, white crystalline powder without obvious yellow tint

· Migration: ≤0.1mg/dm² (YF-651-E), REACH compliant

· Volatile Content: ≤0.5%, low odor, suitable for inks and adhesives

· Absorption Band: 250–350nm, compatible with traditional mercury lamp curing

(IV) Impacts on Downstream Buyers: Ideal Fit for Ink & Adhesive Rigid Demand, Significant Cost Reduction

· Positive Impacts: Buyers of inks, general adhesives and wood coatings targeting Southeast Asia, Middle East and South America gain ultra-high cost-performance at 30% lower prices than imports. Environmental grades deliver low-cost REACH compliance, while flexible small-batch procurement reduces inventory pressure.

· Potential Drawbacks: Purity and batch consistency lag behind Qiangli and Jiu Ri, making the brand unsuitable for high-end electronic and optical scenarios.

IV. Fullaid Chemical (Hubei): High-Purity Customized Process + Precision Control, Preferred for Medical & Food Contact Applications

(I) Production Process: High-Purity Synthesis + Multi-Stage Refining for Low Residuals & High Safety

· Core Route: High-purity benzoin → low-temperature ketalization → multi-stage recrystallization, raw material purity ≥99.9% to eliminate heavy metal and impurity introduction.

· Key Technology: Hydrogen chloride gas catalysis paired with low-temperature crystallization at 5–15°C to minimize side reactions, lifting purity to 99.8%.

· Refining Flow: Triple methanol recrystallization → deep activated carbon decolorization → 0.22μm precision filtration → vacuum drying, heavy metals ≤1ppm, benzoin residuals ≤0.1%.

· Process Characteristics: Medical-grade biocompatibility with ISO 10993 certification, suitable for medical consumables and food packaging.

(II) Supply Stability: 3,000-Ton Capacity + Flexible Customized Production, High Compatibility for Small Batches

· Capacity Scale: Total annual capacity of 3,000 tons, 1,500 tons allocated to UV 651 production, with high-purity grade (FLD-651-HP) accounting for 60%.

· Base Layout: Headquarters in Yichang, Hubei, focused exclusively on high-purity customized production; flexible production lines allow on-demand adjustment of purity, chroma and migration indicators.

· Inventory Guarantee: Permanent stock of 300 tons high-purity grade + 100 tons standard grade, customized orders delivered within 2 weeks.

· Delivery Capacity: Priority scheduling for European & American medical/food orders, complete provision of COA, MSDS and biocompatibility reports with full compliance documentation.

(III) Key Indicators: Ultra-High Medical & Food-Grade Purity, Low Residuals & Superior Safety

· Purity: ≥99.8% (FLD-651-HP, electronic/medical grade)

· Heavy Metals: ≤1ppm (Pb/Hg/Cd), compliant with US FDA 21 CFR 175.300

· Benzoin Residuals: ≤0.1%, low yellowing and low odor

· Migration: ≤0.05mg/dm², highest standard for food-contact materials

· Biocompatibility: Passed ISO 10993 cytotoxicity and skin irritation testing

(IV) Impacts on Downstream Buyers: Perfect Match for Medical & Food Contact Rigid Demand, Fully Compliant Safety Standards

· Positive Impacts: Manufacturers of medical consumables, food packaging and high-end cosmetics satisfy the world’s strictest safety standards with ultra-high purity and minimal migration risks, supported by customized services tailored to unique formulation requirements.

· Potential Drawbacks: High-purity customized grades carry a 20%-25% price premium, elevating procurement costs.

V. Sinocure (Shandong): Export-Oriented Standard Process + Large-Scale Delivery, Top Choice for Global Distributors

(I) Production Process: Standardized Batch Kettle + Stable Refining for Balanced Quality & Cost-Performance

· Core Route: Benzoin + sodium methoxide → ketalization → recrystallization standardized process with mature stable parameters for globally consistent quality.

· Key Technology: Reaction temperature 20–35°C, reaction duration 12h, solvent recycling + continuous filtration to cut costs and stabilize quality.

· Refining Flow: Methanol recrystallization → centrifugal drying → sieving & packaging, purity ≥99.5% (standard grade), ≥99.0% (651-Lite economy grade).

· Process Characteristics: Export-oriented global standard products passing SGS/TUV testing, compatible with global distribution markets.

(II) Supply Stability: 6,000-Ton Capacity + Global Distribution Network, Robust Bulk Delivery Capacity

· Capacity Scale: Total annual capacity of 6,000 tons, 3,000 tons allocated to UV 651 production, with standard grade accounting for 80%, core supplier for global distribution.

· Base Layout: Large-scale continuous 24-hour production at Zibo, Shandong, capacity utilization rate ≥90%.

· Inventory Guarantee: Permanent stock of 500 tons standard grade + 300 tons economy grade, global distribution orders shipped within 7 days.

· Delivery Capacity: Supports 20kg/25kg/50kg multi-specification packaging, 5%-8% price discount for full container (20-ton) bulk orders with priority delivery.

(III) Key Indicators: Global Universal Standards, Balanced Quality & Broad Compatibility

· Purity: ≥99.5% (standard grade), ≥99.0% (economy grade)

· Appearance: White crystalline powder, APHA ≤80

· Melting Point: 64–67°C, aligned with global universal standards

· Light Transmittance (10% toluene solution): ≥95% at 425nm, ≥96% at 450nm

· Volatile Content: ≤0.5%, suitable for general coating, ink and adhesive applications

(IV) Impacts on Downstream Buyers: Top Choice for Global Distributors & Small & Medium Clients, Stable Low-Cost Supply

· Positive Impacts: Global distributors and small & medium coating/ink manufacturers access balanced stable quality at moderate prices with complete global standard certifications eliminating market entry barriers; bulk order discounts reduce overall comprehensive costs.

· Potential Drawbacks: Insufficient performance for high-end electronic and medical scenarios, limited to general industrial applications only.

VI. Concise Comparative Summary of Five Major Brands Across Core Dimensions

(I) Production Process Comparison

· Qiangli New Materials: Closed-loop continuous-flow microreactor, high-purity low-consumption electronic-grade process

· Jiu Ri New Materials: Full industrial chain continuous synthesis, high-transparency anti-yellowing optical fiber-grade process

· Yangfan New Materials: Optimized batch kettle + solvent recycling, low-cost large-scale general-grade process

· Fullaid Chemical: High-purity synthesis + multi-stage refining, low-residual high-safety medical-grade process

· Sinocure: Standardized batch kettle, balanced stable global distribution-grade process

(II) Supply Stability Comparison

· Qiangli New Materials: 12,000-ton dual-base capacity + 1,000-ton permanent stock, 2–3 week lead times, top pick for high-end electronics

· Jiu Ri New Materials: 8,000-ton capacity + global warehouse network, 2-week delivery for Europe & America, ideal for optical fiber and high-end coatings

· Yangfan New Materials: 10,000-ton capacity + flexible scheduling, 7-day delivery, preferred for general emerging market applications

· Fullaid Chemical: 3,000-ton capacity + flexible customization, 2-week delivery, best fit for medical and food contact use

· Sinocure: 6,000-ton capacity + global distribution network, 7-day delivery, top choice for global distributors and small & medium clients

(III) Core Parameter Key Indicator Comparison Table

表格

(IV) Summary of Core Impacts on Downstream Buyers

· High-End Electronic Buyers: Prioritize Qiangli New Materials for stable quality, LED compatibility and full compliance

· Optical Fiber & High-End Coating Buyers: Prioritize Jiu Ri New Materials for high transparency, anti-yellowing properties and European & American market recognition

· Ink & Adhesive Buyers Focused on Emerging Markets: Prioritize Yangfan New Materials for ultimate cost-performance and fast order response

· Medical & Food Contact Buyers: Prioritize Fullaid Chemical for ultra-high purity, low residuals and comprehensive safety compliance

· Global Distributors & Small & Medium Clients: Prioritize Sinocure for balanced quality, robust bulk delivery and controllable costs

For more authentic, objective information on multiple well-known Chinese brands of UV 651, please contact HiSiaddi customer service.

As a new foreign trade service provider driven by both technology transformation and foreign trade services, HiSiaddi has established a "1+2+3+4=1" service system and can supply original factory sources of UV 651 from multiple well-known brands. As a R&D-oriented foreign trade enterprise, HiSiaddi will analyze key purchasing considerations and core indicators from a professional perspective to ease procurement concerns.

If you require more professional, in-depth analysis regarding UV 651 purchasing, please contact HiSiaddi customer service.

I. Comprehensive Considerations from a Global Procurement Perspective

Photoinitiator 651 is an aromatic ketone solid fine chemical raw material with stable chemical properties at room temperature and moderate thermal stability; it volatilizes slowly under medium temperature. It undergoes photochemical reactions when exposed to light and thus requires light-proof storage. It readily absorbs moisture and agglomerates under high-humidity conditions and is classified as a flammable solid chemical, subject to unified global supervision for warehousing, transportation and customs clearance as a flammable solid. The product is regulated by multiple rules including the REACH Regulation, SVHC Substances of Very High Concern, VOC and residual solvent control, heavy metal limits, polycyclic aromatic hydrocarbon (PAH) management, low-odor coating/ink standards, and hazardous chemical import & export supervision. Markets across Europe, America, Japan, South Korea, Southeast Asia and the Middle East enforce clear limit values for residual solvents, volatile components, trace organic impurities, heavy metals and extractables. Some regions impose mandatory requirements on odor and migration volume.

Core quality control indicators for this product: purity of 651, residual synthetic raw materials and isomers, moisture content, ash content, residual solvents (methanol/ethanol/benzene), melting range, high-temperature thermal weight loss, organic volatile content, solution transparency, solid insoluble matter, particle size distribution, heavy metals (lead/cadmium/mercury/hexavalent chromium), PAHs, substance migration volume, storage stability at room temperature, and low-temperature precipitation tendency. Risks vary significantly across application scenarios: in general inks and ordinary coating systems, residual raw materials and excessive moisture & agglomeration will cause unstable curing speed and poor dispersion, resulting in ink dot or film particle defects. For high-end transparent topcoats, residual solvents and insoluble matter as well as poor solution transparency directly lead to film fogging, reduced light transmittance and appearance defects. In low-odor environmentally friendly systems, volatile fractions and residual solvents create strong odors in finished products and excessive VOC levels in workshops. For export-compliant products, heavy metals, PAHs, migrating substances and residual solvents act as hard market access thresholds that directly affect customs clearance. UV coating & ink environmental regulations and hazardous chemical transportation rules differ across countries. Purchasing decisions cannot rely solely on unit price comparison; downstream curing processes, application scenarios, target market regulations and storage & transportation requirements must be comprehensively considered for model selection.

(I) Compliance Qualification Verification: Benchmark Global Regulations to Secure Customs Clearance, Production and Industry Compliance

Compliance documents serve as prerequisites for cross-border customs clearance, hazardous chemical declaration, internal enterprise control, coating & ink factory audits and export environmental filing, making them the primary items to verify before cooperation.

1. Special Certifications and Test Reports Matched to Application Scenarios

· General ink & coating grade for regular printing inks, low-grade wood UV coatings, general photocurable adhesives and ordinary indoor overprint varnishes: provides REACH registration, SVHC screening, hazardous chemical classification identification, basic physical & chemical tests, chromatographic purity, melting range and storage stability reports to meet global general photoinitiator and flammable solid supervision requirements.

· High-end transparent topcoat grade for premium transparent UV topcoats, light-colored wood coatings, high-quality screen printing inks and high-gloss overprint varnishes: supplementary full testing for low residual raw materials, low residual solvents, high solution transparency, zero trace insoluble matter and low precipitation to match appearance and gloss standards for high-end transparent/light-colored photocurable materials.

· Low-odor low-migration eco-grade for coatings used in closed indoor working conditions, peripheral food packaging inks and low-VOC environmentally friendly UV systems: issues test reports for low volatile content, low thermal weight loss, deep solvent removal, low migration and low odor, complying strictly with technical specifications for low-VOC, low-odor photocurable materials.

· Export-compliant special grade for products exported to Europe, America, Japan, South Korea, Australia and fully compliant global UV raw materials: additional full screening for heavy metals, PAHs, migration volume and residual solvent limit tests, plus regional environmental compliance reports to satisfy the strictest global market access requirements for exported photoinitiators.

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Complete Documents for Cross-Border Customs Clearance and Trade Classified as a flammable solid, this product complies with international hazardous goods standards for sea, land and air transportation as well as customs declaration. Our company uniformly provides multi-language SDS safety data sheets, hazardous chemical classification labels and transportation identification reports. Standard customs clearance materials include certificates of origin, batch-by-batch full-item COA quality inspection reports and production traceability records. For high-end transparent grade, low-odor eco-grade and export-compliant special grade orders, supplementary HPLC high-performance liquid chromatography purity profiles, residual solvent, volatile fraction, heavy metal and PAH test reports are provided to support internal audits and official compliance & hazardous goods inspections at overseas ink & coating factories and coating manufacturers.

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Supplier Comprehensive Qualification Screening Priority shall be given to source manufacturers with integrated production capacity including methoxylation synthesis, multi-stage neutralization and water washing, gradient recrystallization refining, deep residual solvent removal, light-proof dust-free crushing and light-proof moisture-proof sealed packaging. Key assessment criteria include separation capacity for structurally similar organic isomers, residual solvent removal efficiency, solution transparency control, powder anti-caking treatment and full-process light-proof process control. Core technical challenges of this product: separating structurally similar organic isomers, thoroughly removing alcohol/benzene residual solvents, eliminating trace insoluble matter to guarantee transparency, preventing premature photosensitive deterioration of raw materials through full light avoidance, and controlling volatile fractions to reduce product odor. Insufficient control in synthesis, water washing, refining and storage will lead to decreased curing efficiency, foggy transparent coatings, pungent odor in finished products, deterioration during long-term storage, inconsistent hazardous goods declaration for exports and excessive environmental indicators. Small sample testing (chromatographic purity, solution transparency, thermal weight loss, curing rate, low-temperature precipitation and simulated light-proof storage & transportation tests) can be conducted in the early cooperation stage to confirm suitability before bulk cooperation.

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(II) Raw Material and Production Process Verification: Lock Synthesis & Refining Procedures to Stabilize Purity and Photocuring Performance

The main product content, organic impurities, residual solvents, transparency, powder state and storage stability are determined by the entire workflow including starting raw materials, synthetic reactions, neutralization water washing, recrystallization, drying, crushing and packaging. These factors also form the core basis for grading different product tiers.

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Upstream Raw Material Quality Inspection High-quality products adopt high-purity benzoin, sodium methoxide and other raw materials alongside low-impurity catalytic systems to complete methoxylation reactions in a closed, light-proof inert environment, minimizing unreacted raw materials, isomers, by-products, various organic solvents and alkaline residues from the source. Subsequent multi-stage neutralization and water washing removes alkaline substances and water-soluble impurities; multi-gradient recrystallization achieves progressive purification; vacuum high-temperature drying thoroughly eliminates residual solvents and free moisture; solution transparency optimization, airflow crushing for particle size regulation and powder anti-caking modification follow. Finished products feature high purity, ultra-low organic impurities and residual solvents, crystal-clear solutions, low volatile content, loose powder, stable photoinitiation efficiency, uniform curing speed, low odor and resistance to precipitation, fully compatible with general ink & coating systems, high-end transparent topcoats, low-odor systems and all export-compliant scenarios. Low-grade products use industrial-grade raw materials with simplified recrystallization and solvent removal workflows, generally suffering from high impurities, heavy solvent residues, poor transparency, strong odor and easy deterioration even under long-term light-proof storage, rendering them unsuitable for high-end transparent coatings, low-odor eco-systems and export-grade products. When purchasing high-end transparent grade and export-compliant grade products, buyers may request quality inspection certificates for starting raw materials and catalysts.

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Classification and Confirmation of Core Production Processes Main complete process route: pretreatment of high-purity raw materials & catalytic system → full-process light-proof closed methoxylation reaction to generate crude 651 → multi-stage neutralization water washing to remove alkaline residues and water-soluble impurities → organic phase separation → primary crude crystallization to eliminate macromolecular impurities → multi-gradient recrystallization for deep removal of raw materials, isomers and residual solvents → vacuum drying for complete elimination of moisture and volatile components → solution transparency stabilization treatment → light-proof airflow crushing for particle size distribution control → powder anti-caking modification → full-index quality inspection → light-proof, moisture-proof inert sealed packaging → cool light-proof warehousing.

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· General ink & coating grade: basic synthesis + single recrystallization + conventional drying and crushing, cost-effective for ordinary inks and low-grade indoor UV coatings.

· High-end transparent topcoat grade: secondary deep recrystallization + extreme solvent removal + transparency optimization, exclusively for transparent/light-colored topcoats and high-gloss inks.

· Low-odor low-migration eco-grade: multi-stage solvent removal + low thermal weight loss treatment + low volatility optimization for closed working conditions and low-odor UV systems.

· Export-compliant special grade: extreme purification + full heavy metal & PAH control + migration limit treatment for globally export-compliant coating and ink raw materials. Formal production lines implement tiered zoning with full light-proof production. High-end and export grades are produced in dedicated light-proof clean workshops, closed refining lines and dust-free crushing equipment to prevent photodegradation and cross-contamination, with strict prohibitions on shipping low-grade products as high-end alternatives.

1. Quality Control and Batch Stability Evaluation This product is manufactured via batch synthesis and recrystallization refining. General ink & coating grade is routinely stocked, while high-end transparent grade, low-odor eco-grade and export-compliant special grade are mostly produced to order. It is recommended to request multi-batch COAs, HPLC liquid chromatograms, residual solvent, moisture, ash and thermal weight loss as well as solution transparency test data, with close monitoring of fluctuation ranges for main content, organic impurities, residual solvents, moisture, transparency and volatile fractions across batches. Long-term cooperation locks in raw materials, reaction parameters and recrystallization processes to ensure consistent photoinitiation efficiency, curing rate, coating transparency and odor performance across batches. Simulated stability data for light-proof, room-temperature, high-low temperature and high-humidity ocean transportation & storage shall be provided to adapt to warehousing and transportation conditions across global regions. Source manufacturers with independent full-process synthesis, water washing, refining and light-proof packaging are preferred; externally repackaged raw materials carry extremely high risks of photodegradation, solvent rebound and transparency fluctuations, especially for high-end and export applications.

(III) Grade and Specification Selection: Match Application Scenarios & Processes to Avoid Parameter Mismatch Risks

Photoinitiator 651 is classified into different specifications based on main purity, organic impurity levels, residual solvent limits, solution transparency, volatility grade, heavy metal/PAH content and migration compliance. Incorrect selection will lead to incomplete curing, foggy transparent coatings, excessive workshop odor, failure of export product compliance and hazardous goods customs clearance. Precise matching with industry field, curing process, working conditions, compliance and storage & transportation requirements is mandatory.

1. Grade Classification by Application Scenario

· General ink & coating grade: ordinary offset/screen printing inks, low-grade wood UV coatings, general photocurable adhesives and regular indoor overprint varnishes.

· High-end transparent topcoat grade: premium transparent UV topcoats, light-colored wood coatings, high-gloss inks and optical-grade overprint varnishes.

· Low-odor low-migration eco-grade: coatings for closed indoor production, peripheral packaging inks and low-VOC environmentally friendly UV systems.

· Export-compliant special grade: globally exported UV coatings & inks, overseas brand OEM products and fully compliant raw material procurement. Cross-tier substitution between different grades is prohibited.

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Physical & Chemical Form Adaptation to Processes The standard form is white to pale yellow loose crystalline powder free of hard agglomerates and visible impurities, with crystal-clear solution state. Core performance metrics to focus on: photoinitiation activity, curing rate, transparency, low volatility, low odor and storage stability. General ink & coating applications prioritize basic purity and curing efficiency; high-end transparent topcoats strictly control organic impurities, residual solvents and solution transparency to guarantee high light transmission, high gloss and zero fogging on coatings; low-odor systems enforce stringent limits on volatile fractions, thermal weight loss and residual solvents to reduce workshop VOC and product odor; export-compliant products require full compliance of heavy metals, PAHs, migrating substances and residual solvents alongside adherence to international flammable solid transportation standards.

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Core Index Agreements in Purchase Contracts Purchase contracts shall clearly stipulate main 651 content, residual raw materials/isomers, moisture, ash, residual solvents, melting range, thermal weight loss, volatile fractions, solution transparency, particle size distribution, heavy metals, PAHs, migration volume, low-temperature precipitation and allowable deviation ranges. High-end transparent topcoat grade strengthens limits for organic impurities, residual solvents and solution transparency; low-odor eco-grade tightens controls on volatile fractions, thermal weight loss and solvent residues; export-compliant special grade adds special requirements for heavy metals, PAHs, migration and hazardous chemical compliance. All indicators shall align with target industry, regional regulations and international flammable solid transportation rules, serving as legal grounds for goods acceptance and dispute resolution upon delivery.

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Packaging and Minimum Order Rules This product is flammable, light-sensitive and moisture-absorbent. Standard packaging consists of light-proof inner film + moisture-proof PE bag + sealed iron drum (hazardous goods standard packaging), with internationally universal flammable solid warning labels affixed to the exterior. High-end and export grades adopt thickened double-layer light-proof inner liners plus sealed iron drums for full light and oxygen isolation. Available packaging sizes: sample bags, 25kg standard hazardous goods drums and IBC totes, customizable on demand. Small sample verification (appearance, solution transparency, curing rate, thermal stability and odor sampling plus formula compatibility testing) shall be completed prior to bulk ordering.

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(IV) Commercial Terms and Comprehensive Cost Accounting: Full-Lifecycle Cost Calculation by Grade for General UV Photoinitiators

UV photoinitiator 651 is a mainstream general-purpose photoinitiator. High-end grades incur higher production costs due to multi-stage recrystallization, deep solvent removal, transparency optimization, light-proof processing, environmental compliance and standardized hazardous chemical handling, so raw unit price alone cannot be used for comparison. Low-cost general grades suffer from high impurities, heavy solvent residues, poor transparency, strong odor and easy photodegradation under light exposure. When used in high-end transparent coatings, low-odor systems or export products, they will cause mass scrapping of finished goods, excessive workshop environmental indicators and customs detention, resulting in extremely high comprehensive usage costs. Full-lifecycle costs must be calculated considering purity stability, impurity & solvent control, transparency consistency, volatility/odor performance, light-proof storage stability, batch consistency, end-product production, compliance and storage & transportation risks.

1. International Trade Quotation Modes

· FOB China Port: covers product cost, international hazardous goods standard light-proof moisture-proof packaging, domestic compliant hazardous chemical warehousing, commodity inspection, export declaration and hazardous goods shipping procedures. International transportation, insurance, destination port hazardous goods customs clearance and local raw material filing are the purchaser’s responsibility, suitable for mass procurement by large ink & coating groups, photocuring manufacturers and overseas traders with optimal comprehensive costs.

· CIF Destination Port: includes ocean freight, insurance, port charges, hazardous goods documents and full compliance operations domestically and overseas, suitable for small-batch procurement by overseas small and medium-sized factories, laboratories and traders. Tiered volume pricing and annual long-term agreement pricing are available to stabilize long-term cooperation costs.

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Payment Terms, Delivery Lead Time and Dispute Definition Mainstream settlement methods: T/T and irrevocable letter of credit. General ink & coating grade is in abundant stock with short lead times; high-end transparent grade, low-odor eco-grade and export-compliant special grade require extended production and delivery cycles due to multi-step refining, full-item precision testing, light-proof hazardous goods packaging and compliance formalities. Contracts shall clearly define dispute judgment criteria: non-compliant main content/organic impurities, excessive solvent/moisture limits, foggy solution with abnormal transparency, severe powder agglomeration, drastically reduced curing rate, excessive odor and mismatched goods. Rules for handling non-compliant hazardous goods packaging, labels and documents shall also be specified, alongside internationally recognized third-party testing institutions, re-inspection and return & exchange procedures. A note shall be added: slight color change under normal light-proof, sealed and cool storage without exceeding standard limits does not affect product performance, clarifying liability boundaries for both parties.

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Warehousing Requirements and Minimum Order Management Uniform storage requirements for all grades: cool, ventilated, dry, fully light-proof sealed storage away from fire sources, heat sources, strong oxidants and high-light areas, managed strictly per flammable solid specifications. High-end and export grades shall be stored in dedicated light-proof hazardous chemical warehouses with zoning separation. Open storage, outdoor stacking and intense light exposure are prohibited, as are mixed storage with oxidants, acids and alkalis. Domestic shelf life shall be stipulated in contracts, and goods shall not be detained at high-temperature, high-light open-air ports for extended periods.

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(V) Packaging, Storage, Transportation and Logistics Control: Special Standards for Flammable Solid Photoinitiators – Light-Proof, Moisture-Proof, Fire-Resistant, Sun-Proof

Core risks during storage and transportation of this product: photosensitive deterioration induced by light, flammability under high temperature, moisture absorption and agglomeration under high humidity, accumulation of volatile residual solvents creating explosion risks and leakage from damaged packaging. Operations must strictly comply with international flammable solid storage and transportation specifications, with core control principles: full light avoidance, cool temperature control, moisture-proof anti-caking, separation from fire & heat sources, strict sun protection and standardized hazardous goods labeling.

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Packaging Standards The full product line adopts hazardous goods-specific iron drums with light-proof inner liners; multi-language flammable solid warning labels, product name, grade, batch number, light-proof/fire-resistance warnings, storage conditions and shelf life are printed on drum bodies. High-end and export grades use thickened light-proof inner liners with double sealing to prevent leakage and light penetration. All packaging undergoes tightness, drop and stacking tests before delivery to meet international sea and land hazardous goods packaging standards.

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Transportation Control Sea, land and air shipments are declared in accordance with international flammable solid regulations, with complete transportation identification documents, SDS and hazardous goods labels provided. Only logistics providers with hazardous goods transportation qualifications are engaged, with vehicle/cargo hold environments maintained cool, ventilated and light-proof under controlled temperatures. Mixed transport with oxidants, flammable liquids, strong acids and alkalis is prohibited; high-temperature summer periods and open-air high-light transportation are avoided. Air freight complies with aviation hazardous goods rules for the corresponding flammable solid classification. Full logistics traceability is implemented, and cargo freight insurance is purchased. Transit warehouses must be compliant light-proof hazardous chemical warehouses with zoning separation.

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On-Site Usage Specifications Upon arrival, goods shall be immediately transferred to compliant light-proof, cool and ventilated hazardous chemical warehouses with packaging integrity, no leakage, no sun exposure traces and complete labels inspected. Sampling and feeding operations shall be carried out in ventilated, light-proof workstations away from fire sources to minimize open exposure time and prevent moisture absorption, photodegradation and solvent volatilization. Drum lids shall be sealed immediately after use with full light protection. Different grades and batches shall be stored separately following first-in, first-out principles. Fire-fighting and ventilation facilities shall be equipped in operation areas, with all flammable solid on-site management specifications followed.

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(VI) Technical Support and After-Sales Service: Focus on Organic Impurities, Residual Solvents, Transparency, Volatility and Storage Stability for Full UV Curing Processes of Inks & Coatings

Organic impurities, residual solvents, solution transparency, volatile fractions and light-proof storage stability of photoinitiator 651 directly determine curing performance, finished product appearance, odor, shelf life and customs clearance compliance. Supporting testing, formulation and process support are critical.

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Application Process Technical Support Samples, complete technical manuals, full-batch HPLC liquid chromatograms, thermal analysis reports and application case studies are provided. Recommended addition ratios, compatibility formulas and storage & workstation operation standards are customized based on customers’ UV ink, various UV coating and photocurable adhesive formulations and curing processes. Optimization solutions are offered for common issues including incomplete curing, foggy coating/ink layers, strong residual odor in finished goods, declining activity during long-term storage and low-temperature precipitation. Target country regulations including REACH, VOC rules, hazardous chemical storage & transportation standards and UV coating & ink industry standards are interpreted simultaneously.

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Delivery Re-Inspection Coordination Re-inspection shall be performed in accordance with international photoinitiator and flammable solid standards. Customers may self-inspect basic items including appearance, powder state, solution transparency and odor, or entrust third-party institutions to test core indicators including main content, organic impurities, residual solvents, moisture, transparency, heavy metals and PAHs. If indicators fail to meet contractual agreements, re-inspection and after-sales procedures shall be implemented per contract and third-party test reports.

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Compliance Document Assistance Multi-language SDS, hazardous goods transportation identification reports, full COAs, original liquid chromatograms, environmental compliance certificates and traceability data are provided on demand to assist local hazardous chemical filing, coating & ink raw material audits, customs inspections and export environmental declaration. Real-time updates on global photoinitiator regulations, flammable solid storage & transportation rules and UV coating & ink industry standard changes are shared regularly.

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II. Core Indicators of Purchasing Focus Segmented by Application Scenario

Five major purchasing categories are divided covering general ink & coating, high-end transparent topcoat, low-odor eco-system, export compliance and international raw material distribution, with clear control priorities specified.

(I) General Ink & Coating Field

Core priorities: stable purity, uniform curing rate, compliant moisture content, loose powder and cost-effectiveness

1. Main 651 content and organic impurities: industrial-grade standard with minimal batch fluctuation

2. Moisture and conventional residual solvents: compatible with regular production to prevent agglomeration and poor dispersion

3. Melting range and basic thermal stability: matched to conventional UV curing and mixing working conditions

4. Powder state and photoinitiation activity: consistent across batches to meet mass production of ordinary inks and primers

5. Light-proof storage stability: no obvious attenuation of curing performance under standardized storage over extended periods

(II) High-End Transparent Topcoat Field

Core priorities: low organic impurities, low residual solvents, high solution transparency, zero trace insoluble matter and high gloss

1. Residual raw materials/isomers and residual solvents (core control items): eliminate coating fogging, haze and reduced light transmittance

2. Solution transparency and insoluble matter: guarantee high light transmission and premium appearance grade for topcoats

3. Volatile fractions and thermal weight loss: reduce odor and coating defects during high-temperature curing

4. Particle size and dispersibility: uniform powder compatible with high-speed coating systems

5. Low-temperature precipitation resistance: no precipitation under low-temperature conditions to stabilize year-round production

(III) Low-Odor Eco-System Field

Core priorities: low volatile fractions, low thermal weight loss, deep solvent removal, low odor and low VOC

1. Volatile fractions, thermal weight loss and residual solvents (core control items): reduce workshop and finished product odor to meet VOC limits

2. Organic impurities: strictly control by-products to minimize odor sources

3. Moisture and powder state: anti-caking performance compatible with continuous production in closed workshops

4. Migration and precipitation tendency: no precipitation during long-term use to enhance product safety

5. Batch consistency: stable odor and volatile indicators for compliant mass production

(IV) Export Compliance Field

Core priorities: compliant heavy metal levels, low PAHs, low migration, solvent compliance and complete hazardous goods documents & packaging

1. Heavy metals, PAHs and migration volume (primary rejection criteria): meet mandatory global export environmental standards

2. All residual solvents: strictly aligned with regional VOC and solvent limit regulations

3. Organic impurities and volatile fractions: fully comply with local coating & ink raw material specifications

4. Packaging, labels and hazardous goods documents: complete compliance to ensure smooth sea, land and air transportation plus customs clearance

5. Full set of qualification reports: testing, certification and transportation documents available to pass official audits and inspections across countries

(V) International Raw Material Distribution Field

Core priorities: stable storage & transportation performance, intact hazardous goods packaging, complete documents and consistent batch quality

1. Storage & transportation stability: unchanged purity, activity and transparency under ocean shipping light and temperature-humidity fluctuations

2. Packaging and labeling: intact sealed hazardous goods iron drums with clear hazard warning labels, free of leakage and damage

3. Quality consistency: unified indicators across batches of the same grade to match downstream customers globally

4. Supporting documents: complete SDS, transportation identification, COAs, chromatograms and compliance reports to support multi-country customs clearance and audits

For more professional and in-depth analysis on UV 651 purchasing, please contact HiSiaddi customer service.