| HS Code | 584156 |
| 产品名称 | 光引发剂PCB Dry Film Special Photoinitiator |
| 化学类型 | 自由基型光引发剂 |
| 外观 | 浅黄色粉末或结晶固体 |
| 吸收波长范围 | 340-420 nm |
| 溶解性 | 溶于丙酮、丙二醇甲醚醋酸酯等有机溶剂，不溶于水 |
| 光敏性 | 高光响应，曝光能量20-60 mJ/cm² |
| 热稳定性 | 分解温度大于160°C |
| 储存稳定性 | 室温避光密封保存12个月 |
| 挥发性 | 常温低挥发性 |
| 相容性 | 与丙烯酸酯单体、环氧树脂及干膜组分相容 |
| 固化速度 | UV-LED或高压汞灯下快速固化 |
| 应用 | 用于PCB干膜光刻胶的光聚合引发 |
As an accredited 光引发剂PCB Dry Film Special Photoinitiator factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Packed in 25 kg moisture-proof aluminum foil bags with nitrogen flushing, ensuring stable storage and safe transport of the PCB Dry Film Special Photoinitiator. |
| Container Loading (20′ FCL) | 20′ FCL container loading: photoinitiator packed in sealed drums, palletized and secured, maximizing safe transport capacity. |
| Shipping | 本产品为光引发剂，运输时需避光、防潮、密封包装，远离热源和火源。建议采用常温干燥运输，避免剧烈挤压和暴晒。若为粉末或液态，均按普通化学品安全操作。快递或物流均可，但需确保包装完好，防止泄漏污染。 |
| Storage | Store in a cool, dry, well-ventilated area away from direct sunlight, UV light, heat, and ignition sources. Keep the container tightly sealed to prevent moisture absorption and contamination. Avoid contact with oxidizing agents. Use appropriate personal protective equipment when handling. Follow manufacturer’s recommendations for shelf life and disposal. |
| Shelf Life | Typical shelf life is 12 months when stored unopened in a cool, dry, dark place, away from sunlight and moisture. |
Within a Class 3 multilayer line, the dry film must maintain 25 µm line/space features through a horizontal shower etch bath containing cupric chloride at 2.0–2.5 mol/L HCl and 45–55 °C; the photoinitiator package determines whether the resist sidewall remains intact or yields an undercut greater than 1.0 mil. Finished-layer acceptance is inspected to IPC-A-600H Class 3 after etch, and the stripping step is controlled under RoHS Directive 2011/65/EU Annex II and REACH Regulation (EC) No 1907/2006 Annex XVII for halogenated residue and sensitizing photoinitiator components. The addition ratio for acid-etch dry films is typically 2.0–3.2 wt% of total dry-film solids, with a secondary thioxanthone sensitizer at 0.2–0.5 wt% when the exposure source is a 365 nm metal halide lamp, shifting the absorption tail and reducing top-to-bottom cure differential. In production, the dry film is laminated onto cleaned copper foil at 100–115 °C roll temperature and 1.5–3.0 bar nip pressure, exposed through a phototool at 60–120 mJ/cm², developed in 0.85–1.0 wt% sodium carbonate at 29–32 °C, then etched and stripped in 2.5–3.5 wt% sodium hydroxide at 50–55 °C. If the lamination temperature exceeds 115 °C, photoinitiator crystallization at the interface produces microvoids that appear as post-etch notch fractures; if the loading falls below 2.0 wt%, the resist loses crosslink density in the lower third of the film and generates crescent-shaped edge lifting at a measured etch factor below 2.5, where etch factor is conductor thickness divided by lateral undercut. End-use terminal product types include multilayer PCB inner layers for server backplanes, base-station transceivers, and industrial control boards where Class 3 annular ring and conductor width retention are mandatory.
A 38 µm negative-acting dry film, laminated at 105–115 °C onto a plated-copper through-hole panel, is used as a plating resist in acid copper deposition; the photoinitiator must produce a high crosslink density at the base of the film without excessive top-surface brittleness. Batch-to-batch variation in dry film thickness of ±2 µm shifts the required exposure dose by approximately 10–15 mJ/cm²; on horizontal laser direct imaging equipment with a 405 nm diode line, the measured dose window is 70–140 mJ/cm². In this formulation, the photoinitiator loading is raised to 2.8–4.5 wt% of total dry-film solids because the plated copper bath attacks the resist/copper interface and the lower portion of the film must remain insoluble for 45–90 min in a sulfuric acid-copper sulfate electrolyte containing 60–100 g/L CuSO₄·5H₂O, 180–220 g/L H₂SO₄, and 40–70 ppm chloride ion at 22–28 °C and 1.5–2.5 A/dm². Adhesion after plating is tested by ASTM D3359-23 cross-cut with a required rating of 5B, and the finished pattern plating line is qualified to IPC-6012 Class 3 with RoHS Directive 2011/65/EU Annex II lead restrictions verified for the tin or nickel etch mask that replaces tin-lead. The downstream flow includes lamination, exposure, 0.9–1.1 wt% sodium carbonate development at 29–32 °C, acid copper pattern plate, tin or nickel etch-mask deposition, resist stripping in 3–5 wt% sodium hydroxide at 50–55 °C, and base-copper flash etch. Chloride levels above 80 ppm in the copper bath correspond to field-reported resist lifting at the adhesion margin and generate plating slivers; storage of the unexposed dry film above 25 °C accelerates dark polymerization and narrows the exposure window by 5–10 mJ/cm² per week. Terminal finished products are HDI smartphone mainboards, automotive engine-control units, and advanced multilayer boards requiring copper through-hole filling and Class 3 thermal stress performance.
Because the bottom of a 15 µm dry film receives attenuated irradiance through the already-cured top layer, the rate-limiting location for monomer conversion in modified semi-additive processing is the resist-copper interface; the resist must survive pattern copper plating while the top surface remains dimensionally stable for line-space control below 20 µm. In this application, the addition ratio is typically 3.0–5.0 wt% of total dry-film solids, with the photoinitiator package split between an alpha-hydroxy ketone and a 405 nm phosphine oxide to maintain simultaneous surface and bottom cure; published data for this specific configuration is limited, so the ratio is usually adjusted by the dry-film manufacturer for laser direct imaging compatibility. Process equipment includes a 5 µm spot direct imaging system with alignment accuracy of ±1.5 µm and a 15–25 µm dry film laminated onto 3 µm carrier copper. The exposure dose window is 80–150 mJ/cm² at 405 nm; below that range, development leaves scum at the copper-resist boundary, and above that range, top-surface blooming raises the top width by more than 2 µm relative to the bottom width. Typical development uses 0.8–1.0 wt% sodium carbonate at 29–31 °C, followed by pattern electroplating of copper to the target trace thickness and flash etching of the 3 µm seed layer. Compliance is verified through IPC-6016 Class 3 for high-density interconnect structures and through IPC-A-600H Class 3 after flash etching; extractables from residual photoinitiator must remain below limits specified in REACH Regulation (EC) No 1907/2006 Annex XVII. A processing limit is the condition of the dry film just after lamination at 100–115 °C: if the film is held at room temperature for more than 8 days, dark reaction at the surface widens the bottom-to-top cure gap and produces a measurable sidewall angle collapse from 88° to 85°. End-use terminal product types are IC package substrates for ball-grid array and chip-scale packages, fine-pitch flip-chip substrates, and high-density interconnect boards for mobile processors.
Flexible polyimide laminates carrying rolled-annealed copper conductors form the substrate for a photoimageable coverlay in which the photoinitiator package is adjusted for oxygen inhibition at the air interface and for thermal stability through subsequent lead-free solder assembly. The addition ratio in this scenario is 2.0–3.5 wt% of total dry-film solids; pigmented or halogen-free grades often sit at the lower end of that range because dispersed pigments attenuate 365 nm light and shift the required exposure dose upward by 10–20%. Vacuum lamination at 80–100 °C is followed by exposure at 365 nm and development in 0.9–1.1 wt% sodium carbonate at 29–32 °C, then final cure at 150–180 °C. Oxygen inhibition at the resist-air boundary appears as a tacky top surface when the dose falls below approximately 100 mJ/cm²; a nitrogen-rich lamination environment or a thin oxygen-barrier topcoat eliminates this surface undercure. Compliance for the coverlay is evaluated to IPC-6013 Class 3 for flexible printed boards, with flammability controlled to UL 94 V-0 and ionic cleanliness verified after 85 °C/85% RH aging for 168 h. Formulators avoid combining this photoinitiator package with secondary amine synergists beyond 0.2 wt% because amine-induced dark reaction lowers storage shelf life at 25 °C from 12 months to approximately 4–6 months; refrigeration at 5–10 °C is required if the amine content must be increased for cure-depth recovery. Terminal products include flexible printed circuits for automotive camera modules, wearable medical electrode arrays, and rigid-flex handheld devices where repeated dynamic flexing must not crack the cured coverlay at 180° bend radius.
Prior to solder mask qualification, the photoinitiator effect is evaluated by measuring the resolution of dam openings and the adhesion of the cured film to copper after a 288 °C solder float test. Dry film solder mask formulations in this category typically carry a photoinitiator addition of 1.5–3.0 wt% of total dry-film solids; loadings above 3.0 wt% increase residual photoinitiator concentration after final cure and can reduce the solder-resistance threshold of the mask at the 288 °C float immersion, particularly when the mask thickness exceeds 25 µm. The downstream process uses vacuum lamination at 70–90 °C onto an etched flexible or rigid board, followed by UV exposure at 365 nm, spray or puddle development in 0.9–1.1 wt% sodium carbonate at 29–33 °C, and final thermal cure at 150–180 °C. Compliance testing is performed to IPC-SM-840E, with flammability rated to UL 94 V-0 and end-product finish inspected to IPC-A-600H Class 3. A process limitation for photoinitiator selection is the resolution of solder dams: below 50 µm opening width, pigment scattering and photoinitiator attenuation through the film thickness cause inconsistent sidewall cure and intermittent dam lift during solder leveling; published data for specific narrow-dam configurations is limited, so qualification panels should include the minimum dam width and largest pad opening of the actual build. Terminal product types include flexible printed circuits for wearable electronics, medical diagnostic devices, and rigid-flex avionics where permanent solder mask adhesion and 288 °C solder-float resistance are mandatory.
Drilled flexible and rigid multilayer panels with 0.20–0.30 mm through-holes require a dry film that spans the hole without rupture during vacuum lamination at 70–90 °C and later survives the spray-etching pressure of cupric chloride at 45–55 °C; the photoinitiator package influences tensile elongation of the cured film and its tendency to crack at the hole rim. The addition ratio for tenting grades is 2.2–3.5 wt% of total dry-film solids, with the lower end used for 0.30 mm holes and the upper end for 0.20 mm holes where the cured film must resist sagging and etchant ingress. Exposure through a phototool at 365 nm typically requires 60–110 mJ/cm², and development is carried out in 0.85–1.0 wt% sodium carbonate at 29–31 °C. Compliance is checked to IPC-6012 Class 3 for plated-through-hole integrity and, after stripping, to RoHS Directive 2011/65/EU Annex II for restricted residues. A specific processing limit appears at the hole rim: loadings above 3.5 wt% raise crosslink density enough to reduce elongation at break below 5% when measured by ASTM D638-14 on a free film, and field data from horizontal etch lines show rim cracking at the 10–15 min residence time when the film is overexposed by more than 20%. Terminal product types include double-sided and multilayer plated-through-hole boards for consumer electronics, instrumentation, and industrial power-control modules where through-hole tenting eliminates separate plugging processes.
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Designated as 光引发剂PCB Dry Film Special Photoinitiator, the product is a solid photoinitiating system formulated for acrylate-based negative-tone dry film photoresists used in printed circuit board outer-layer imaging, inner-layer imaging, and solder mask lamination. The active component is an α-aminoacetophenone derivative combined with a tertiary amine co-initiator in a weight ratio that suppresses surface oxygen inhibition during ultraviolet exposure. Its principal absorption bands are centered at 365 nm and 385 nm, with a secondary shoulder near 405 nm. The product is supplied as a pale yellow crystalline solid. Published data for this specific configuration is limited; the following parameters are drawn from manufacturer certificate-of-analysis templates and batch-level quality records used in PCB fabrication qualification.
In the dry film photopolymer matrix, the photoinitiator is dissolved in a mixture of bisphenol A epoxy acrylate, trimethylolpropane triacrylate, and a carboxylated acrylic binder. The carboxyl groups provide alkaline solubility in the unexposed regions. During exposure, the photoinitiator absorbs incident photons and generates free radicals that crosslink the acrylate double bonds. Because the dry film is laminated to a reflective copper surface, back-reflected radiation contributes to bottom cure; the photoinitiator absorption at 365 nm is balanced to avoid excessive top-surface cure. The optical density of a 25 µm dry film at 365 nm is maintained between 0.30 and 0.50 absorbance units to stabilize the top-to-bottom cure gradient.
The photoinitiator is specified by high-performance liquid chromatography assay, thermal analysis, and solution optical density. Typical acceptance limits are listed in Table 1. The melting range is determined by capillary method; loss on drying is measured at 105 °C for 2 h. Solubility is tested in propylene glycol monomethyl ether acetate (PGMEA) at 25 °C because this solvent is the dominant carrier in dry film casting. The product is soluble at ≥ 25 g/100 g in PGMEA, which permits masterbatch preparation without high-shear dispersion. Viscosity of a 10 wt% solution in PGMEA at 25 °C is typically 3–8 mPa·s. Batch-to-batch photospeed is controlled by monitoring the optical density at 365 nm of a 0.01 g/L acetonitrile solution; the acceptance range is 0.45–0.55 absorbance units.
| Parameter | Test condition | Acceptance limit |
|---|---|---|
| Appearance | Visual against light | Pale yellow crystalline solid |
| Assay | HPLC, area% | ≥ 99.0 |
| Melting range | Capillary, 1 °C/min | 72–75 °C |
| Loss on drying | 105 °C, 2 h | ≤ 0.10 % |
| Ash | Muffle furnace 800 °C | ≤ 0.05 % |
| Absorption maximum | UV-Vis in acetonitrile | 365 ± 5 nm, 385 ± 5 nm |
| Solubility in PGMEA | Gravimetric, 25 °C | ≥ 25 g/100 g |
| Heavy metals | ICP-OES | ≤ 5 mg/kg |
The supplier certificate of analysis is generated under ISO 9001:2015; test methods are internal but cross-referenced to applicable pigment test standards where available. The non-volatile fraction is controlled to avoid plasticization of the dry film after solvent removal. Chloride and sulfate impurities are maintained below 10 mg/kg because ionic residues can increase copper corrosion under humid aging.
At lamination temperatures of 95–110 °C, a hot-roll laminator applies the resist to copper-clad laminate at 0.3–0.5 MPa nip pressure and 1.0–2.0 m/min roller speed. The photoinitiator does not undergo measurable thermal decomposition under these conditions; thermogravimetric analysis at 10 K/min under nitrogen shows 5% mass loss at 180–200 °C, which is above the lamination window. This thermal margin allows the photoinitiator to survive hot-roll lamination without measurable decomposition. In a double-sided lamination line running at 3.0 m/min with a 5 kW metal halide lamp, step retention remains within ±0.5 step across a 300 mm panel width.
On a production casting line with a die width of 1200 mm and line speed of 8–15 m/min, the photoinitiator solution is metered into the resist mix through a mass flow controller with an accuracy of ±0.1 wt%. Residual solvent after oven drying at 110 °C for 3 min is maintained below 1.0 wt% to prevent surface tack. In a 25 µm dry film containing 2.0–5.0 wt% photoinitiator relative to total acrylate monomer, the exposure dose required to retain step 7–9 on a 21-step Stouffer wedge is typically 20–40 mJ/cm² at 365 nm. At loadings below 2.0 wt%, surface cure is insufficient and the developed resist shows undercut at the copper interface; at loadings above 5.0 wt%, strong upper-layer absorption reduces bottom cure and narrows the exposure latitude to ±5 mJ/cm².
In a twin-screw extruder with a 40:1 L/D ratio and zone temperatures of 85–105 °C, the photoinitiator is dispersed into the resist premix at 200–300 rpm. Because the product is soluble in PGMEA, high-shear dispersion is not required. Premature crosslinking is not observed when the melt temperature remains below 130 °C. Additional amine-based additives beyond the formulated ratio are not recommended because excess tertiary amine accelerates dark reaction and reduces room-temperature shelf life.
Direct imaging systems using 405 nm laser diodes or LED arrays require a different dose balance than mercury arc exposure. The photoinitiator absorbs less strongly at 405 nm than at 365 nm; therefore the effective surface dose must be raised to 60–80 mJ/cm² for equivalent step retention. However, the lower absorption at 405 nm improves through-film cure because less radiation is consumed in the top 5 µm of the resist. Line width retention under a 12 µm air gap is maintained at 50 µm line/space geometry when the exposure machine is fitted with a 2.5 kW laser module and the substrate is vacuum-held. Published data for this specific configuration is limited; the cited values are from qualification runs on a direct imaging unit with a 405 nm source and 25 µm dry film.
Oxygen inhibition at the resist surface is mitigated by the tertiary amine co-initiator, which forms a radical scavenging pathway for peroxy radicals. The result is a surface-to-bottom cure gradient of ≤ 1.0 Stouffer step at 25 µm thickness. If the air gap exceeds 15 µm, the surface dose must be increased by 10–15 mJ/cm² to compensate for oxygen diffusion. The product is also compatible with exposure units calibrated to ISO/IEC 17025. At 35 °C and 55% relative humidity, the dry film surface may absorb moisture; this slows radical polymerization and requires a 5–10 mJ/cm² dose increase. Pre-drying at 60 °C for 10 min is recommended when relative humidity exceeds 60%.
The product differs from benzophenone/tertiary amine systems by generating both radical species through intramolecular α-cleavage and hydrogen abstraction, which reduces the sensitivity to dissolved oxygen at the resist surface. Compared with thioxanthone/amine systems, the product contains no sulfur-bearing chromophore and therefore shows lower yellowing in the developed film. Compared with hexaarylbiimidazole/leuco dye systems, the product has faster photospeed at 365 nm but a shorter dark-stability window after exposure. The carboxylated acrylic binder acid value interacts with the photoinitiator amine co-initiator. Acid values above 150 mg KOH/g can partially quench the co-initiator and reduce surface cure. Formulators typically maintain the acid value between 90–120 mg KOH/g to preserve alkaline developability without suppressing free-radical generation. Table 2 summarizes process-relevant comparisons.
| System | Primary absorption | Surface cure | Exposure dose at 365 nm for step 7–9 | Solubility in PGMEA | Yellowing |
|---|---|---|---|---|---|
| PCB Dry Film Special Photoinitiator | 365/385 nm | High | 20–40 mJ/cm² | ≥ 25 g/100 g | Low |
| Benzophenone/amine | 250–350 nm | Moderate | 50–100 mJ/cm² | High | Moderate |
| Thioxanthone/amine | 360–400 nm | High | 30–60 mJ/cm² | Moderate | Moderate |
| HABI/leuco dye | 350–420 nm | Moderate | 30–60 mJ/cm² | Low | Low |
Alkaline development is performed in 0.8–1.0 wt% anhydrous sodium carbonate at 30–32 °C. The breakpoint is controlled at 35–50% of total developer length to prevent scumming while preserving sidewall geometry. For a 25 µm dry film, a post-exposure hold of 10 min at 23 °C increases step retention by 0.5–1.0 step, but a 60 min hold causes radical diffusion and loss of fine-line resolution. The product dark reaction is therefore manageable only within a production scheduling window of ≤ 20 min between exposure and development. Panels failing the step wedge acceptance window are quarantined and reworked by stripping in 3 wt% sodium hydroxide at 45 °C.
Storage of the solid photoinitiator requires a relative humidity below 60% and a temperature below 35 °C. Containers should be purged with nitrogen after opening. Contact with strong oxidizers, peroxides, or concentrated acids must be avoided because premature radical generation or chromophore degradation may occur. The product is not classified as a flammable solid under normal transport conditions, but its dust may form an explosive mixture with air; housekeeping should follow IEC 60079-10 zone-classification principles for combustible dust. The product is incompatible with cationic photoinitiators in the same formulation because the amine co-initiator neutralizes the Brønsted acid catalyst.
Under RoHS Directive 2011/65/EU, the product contains no lead, cadmium, mercury, hexavalent chromium, PBB, or PBDE within the meaning of Annex II. REACH registration is maintained under EC 1907/2006, and the product is listed in the supplier safety data sheet with a specific concentration of residual solvent below 0.1 wt%. Because the product contains no deliberately added halogens, it can be used in formulations targeting IPC-4101B halogen-free laminates; however, the final resist film must be qualified by ionic contamination testing per IPC-TM-650 method 2.3.25.
