| HS Code | 767509 |
| Product Name | Toluene Electronic/EL Grade |
| Cas Number | 108-88-3 |
| Chemical Formula | C7H8 |
| Molecular Weight | 92.14 g/mol |
| Appearance | Clear colorless liquid |
| Purity | >=99.9% |
| Boiling Point | 110.6 °C |
| Melting Point | -95 °C |
| Flash Point | 4.4 °C (closed cup) |
| Density | 0.865 g/cm3 at 20 °C |
| Vapor Pressure | 28.4 mmHg at 25 °C |
| Vapor Density | 3.18 (air = 1) |
| Refractive Index | 1.496 at 20 °C |
| Solubility In Water | Slightly soluble (0.47 g/L at 20 °C) |
| Dielectric Constant | 2.38 at 25 °C |
As an accredited Toluene Electronic/EL Grade factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Toluene Electronic/EL Grade, 4 L, packaged in a nitrogen-purged amber glass bottle with PTFE-lined closure for purity. |
| Container Loading (20′ FCL) | 20′ FCL: load electronic-grade toluene in sealed drums/IBCs, secure and label properly, ensure ventilation, and follow hazmat regulations. |
| Shipping | Toluene Electronic/EL Grade ships as a hazardous flammable liquid. It must be transported in grounded, UN-approved containers, away from ignition sources and oxidizers. Proper labeling, documentation, and compliance with DOT/IMDG regulations are mandatory. Ensure secure, leak-proof packaging to prevent spills and vapor exposure during transit. |
| Storage | Store Toluene Electronic/EL Grade in a cool, dry, well-ventilated area away from heat, sparks, open flames, and strong oxidizers. Keep containers tightly sealed to prevent contamination and evaporation, protected from sunlight and physical damage. Use approved, grounded flammable-liquid storage cabinets, and follow all electrical grounding and regulatory requirements. |
| Shelf Life | Shelf life is typically three years when stored in original sealed containers under recommended, dry conditions. |
In 300 mm semiconductor coater/developer tracks, electronic-grade toluene with water content held below 50 ppm and total trace metal burden below 20 ppb is metered into edge-bead-removal solvent blends at 70–85 wt%, with the remaining 15–30 wt% typically composed of propylene glycol monomethyl ether acetate or n-butyl acetate. Industry compliance for this application is governed by cleanroom particulate limits in ISO 14644-1:2015 Class 4 for chemical dispense zones, distillation range verification per ASTM D1078-11 with initial boiling point above 110.0 °C and dry point below 111.5 °C, and platinum-cobalt color checks per ASTM D1209-05 at ≤5 APHA. The downstream production process occurs on an in-line coater module integrated with a photoresist track: a 300 mm wafer rotates at 500–1,500 rpm while the edge-bead-removal nozzle dispenses the toluene-containing solvent at 0.2–0.5 mL/s against the wafer edge; the dissolved resist bead is removed before post-apply bake at 90–110 °C on a hotplate with ±0.3 °C temperature uniformity. Terminal finished products are patterned semiconductor wafers for complementary metal-oxide-semiconductor logic, dynamic random-access memory, 3D NAND flash, and microelectromechanical systems, where edge bead residues are considered yield-limiting defects at critical dimensions below 45 nm. The table below summarizes representative electronic-grade toluene control parameters for this semiconductor use.
| Parameter | Test method | Typical EL grade limit | Application impact |
|---|---|---|---|
| Purity by GC | ASTM D1078-11 distillation range, GC assay | ≥99.9 wt% | Nonvolatile residue on wafer edge |
| Water content | Karl Fischer coulometry | ≤50 ppm | Photoresist hydrolysis control |
| Evaporation residue | Gravimetric after 110 °C | ≤5 ppm | Post-develop defect density |
| Total trace metals | ICP-MS | ≤20 ppb total, ≤10 ppb per transition metal | Gate oxide integrity and carrier lifetime |
| Platinum-cobalt color | ASTM D1209-05 | ≤5 APHA | Resist film transmission uniformity |
In flexible organic light-emitting diode display manufacturing, toluene EL grade is used as a co-solvent in polyimide precursor varnishes for plastic substrate formation and alignment-layer coating; the addition ratio is maintained between 15 wt% and 25 wt% of the total varnish mass, because below 15 wt% the varnish can exceed 4,000 cP and produce slit-die streaking, while above 25 wt% the flashpoint of the mixture drops enough to require upgraded exhaust classification. Compliance references include ISO 14644-1:2015 Class 5 for coating booths, ASTM D1209-05 for color control at ≤5 APHA to avoid yellowing-assisted pinhole formation in low-temperature cured layers, and REACH Regulation (EC) No 1907/2006 Annex XVII entry 48 restrictions, which do not prohibit industrial polyimide solvent use but impose concentration labelling duties in the European Economic Area. The production process uses a slit-die coater on Gen 6 glass at 1,500 × 1,850 mm substrate size, with pre-coating filtration through a 0.1 µm polytetrafluoroethylene membrane at 23 °C, vacuum degassing at −80 kPa for dissolved oxygen reduction, and multi-stage curing from 80 °C to 350 °C under nitrogen. Terminal finished products include flexible OLED display modules, foldable smartphone cover windows, and rollable television substrates, where residual solvent heterogeneity is monitored by thermal desorption-gas chromatography at ≤2 ppm toluene in the cured polyimide film.
Positive-tone diazonaphthoquinone/novolac photoresists for thin-film transistor liquid crystal display photolithography are diluted with electronic-grade toluene at 5–15 wt% when incoming resist solids content requires reduction from 28 wt% to 24 wt% for coater compatibility. Compliance here requires solvent purity of ≥99.9 wt%, water below 50 ppm, and particulate counts below 20 particles/mL at a 0.5 µm minimum size in an ISO 14644-1:2015 Class 5 dispense room; distillation range is checked by ASTM D1078-11, and the lot is released only when platinum-cobalt color per ASTM D1209-05 remains ≤5 APHA. The downstream production process transfers the diluted photoresist to a spin coater on a TFT array line, where a 4,000 rpm main spin step with 0.5–1.5 mL dispense produces a 1.2–2.0 µm film, soft-baked at 90–110 °C for 90 s, exposed through a 4x stepper at 365 nm, and developed in aqueous tetramethylammonium hydroxide. Terminal finished products include amorphous silicon and low-temperature polycrystalline silicon TFT backplanes for liquid crystal display panels, monitor glass, and television panels, where residual solvent variation across the glass substrate must remain below 1.5% film thickness non-uniformity after development.
For organic semiconductor and printed-electronics formulations, toluene EL grade functions as a solvent for regioregular poly(3-hexylthiophene) and related conjugated polymers at total solids loadings of 0.5–2.0 wt%, where the solvent boiling range and surface tension define wet-film leveling during slot-die coating. Industry compliance in this segment derives from ISO 14644-1:2015 Class 5 cleanroom handling, ASTM D1209-05 color control at ≤5 APHA, and ASTM D1078-11 distillation range verification for solvent lot-to-lot uniformity. In slot-die coating, the ink is supplied through a 0.45 µm polytetrafluoroethylene cartridge filter to a slot-die head with 50–100 µm shim gap, deposited onto poly(ethylene naphthalate) or glass at 1–5 m/min web speed, then dried at 60–90 °C for 5–15 min under nitrogen. Terminal finished product types include organic thin-film transistor backplanes for e-paper, organic photodiode arrays, printed antenna and sensor electrodes, and solution-processed photovoltaic modules; published data for high-volume printed transistor threshold voltage stability is limited, so incoming solvent metal content is typically controlled below 10 ppb per transition metal to prevent semiconductor doping drift.
In precision fibre optic connector and high-reliability military/aerospace interconnect manufacturing, EL grade toluene is employed in vapour phase cleaning and ultrasonic degreasing at 80–90 wt% concentration in blends with anhydrous ethanol or as a neat condensate, specifically where halogenated solvents are excluded by customer material declarations. Compliance for this cleaning application includes ASTM D1078-11 for solvent distillation range, ISO 14644-1:2015 Class 5 for final assembly environments, IPC J-STD-001H Section 8.3.1 for soldered assembly cleanliness requirements, and RoHS Directive 2011/65/EU for final electronic product restrictions. The production process operates a two-sump vapour degreaser with immersion sump temperature at 110 °C, vapour zone maintained at 110–111 °C, cooling coils at 15–20 °C, and ultrasonic transducers at 40 kHz with 0.6 W/cm² power density; parts are dried in freeboard and transferred to ionized-air stations before assembly. Terminal finished product types include ceramic ferrule fibre optic connectors, optoelectronic transceivers, and military-specification circular connectors, where post-cleaning ionic contamination is measured by resistivity of solvent extract below 1.5 µg NaCl equivalence/cm².
Electronic chemical lot certification uses toluene EL grade as a gravimetric and ICP-MS dilution matrix for trace metal verification of photoresist solvents, edge bead removers, and polyimide intermediates; the solvent is added to calibrant and sample at 1:10 to 1:50 mass dilution ratios, depending on the expected metal concentration. Compliance with ISO 17025:2017 clause 7.7 for measurement traceability, ASTM D1078-11 for solvent purity, and ASTM D1209-05 for color control protects the analytical blank. The downstream process uses inductively coupled plasma mass spectrometry with a perfluoroalkoxy nebulizer and platinum cones, running at 1,100 W forward power and 0.9 L/min nebulizer flow, with matrix-matched calibration standards prepared by mass dilution in a Class 5 cleanroom. Terminal finished product types are certified electronic solvent lots, photoresist diluent batches, and QC reference standards released for semiconductor and display manufacturing; a lot with blank counts above 3 counts per second for 23Na or 56Fe is rejected or re-distilled.
Competitive Toluene Electronic/EL Grade prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8615365186327 or mail to admin@ascent-chem.com.
We will respond to you as soon as possible.
Tel: +8615365186327
Email: admin@ascent-chem.com
Flexible payment, competitive price, premium service - Inquire now!
Toluene Electronic/EL Grade is a high-purity aromatic hydrocarbon solvent specified for semiconductor, flat-panel display, and microelectronic manufacturing where trace contamination control is the principal acceptance criterion. The material is defined by C₇H₈ and CAS 108-88-3, with typical lot-release parameters that include a gas-chromatographic assay of at least 99.9%, water content not exceeding 100 ppm by coulometric Karl Fischer titration following ASTM E1064-16, evaporation residue not exceeding 1 ppm, and specified metal impurities in the low- to sub-ppb range. The Electronic/EL designation separates this product from ACS reagent, HPLC, and technical-grade toluene because semiconductor-critical elements such as sodium, potassium, iron, chromium, and copper are measured by inductively coupled plasma mass spectrometry and limited on a lot-by-lot basis. In production, the solvent is dispensed from electropolished stainless steel or fluoropolymer containers through hydrophobic point-of-use membranes rated at 0.05 µm or 0.1 µm before contact with photoresist, wafer surfaces, or metal interconnects. Residual solvent films can persist in recessed features after spin-off; therefore low non-volatile residue and low acidity reduce organic or chloride-bearing deposits during subsequent thermal processing. The product is supplied under grade descriptors such as VLSI, CMOS, or Electronic/EL, but these terms are not globally harmonized model numbers. Qualification is performed using certificate-of-analysis data rather than trade nomenclature, and actual lot data are requested because supplier internal limits may be tighter than published minimums.
| Parameter | Electronic/EL | HPLC | ACS Reagent | Technical |
|---|---|---|---|---|
| Assay by GC-FID | ≥ 99.9% | ≥ 99.8% | ≥ 99.5% | Supplier-dependent |
| Water by coulometric Karl Fischer titration | ≤ 100 ppm | ≤ 100 ppm | Supplier-dependent | Not controlled |
| Residue after evaporation | ≤ 1 ppm | ≤ 5 ppm | ≤ 10 ppm | Not controlled |
| Acidity | Supplier-tightened, typically below ACS threshold | Not specified | ≤ 0.0005 meq/g | Not specified |
| Critical trace metals such as Na, K, Fe, Ca | ≤ 1 ppb per element on certificate of analysis | Not specified | Not specified | Not controlled |
At the point of qualification, the distinguishing technical issue is not high chromatographic purity alone. A solvent may show 99.9% assay and still contain part-per-million sodium or part-per-billion metallic contamination that is incompatible with gate oxide or low-k dielectric processing. HPLC-grade toluene is controlled for low UV background and low residue, but its metal and particle specifications are generally absent or unsuitable for wafer-fab use. ACS-grade toluene carries wet-chemical and residue limits sufficient for analytical work, but its permitted residue levels are significantly higher than those accepted in advanced semiconductor cleaning. Technical-grade toluene is produced for blending, synthesis, or general industrial use and is not suitable for electronic contact; it can contain rust, dissolved metals, water, sulfur, and polymerizable impurities that would contaminate a photoresist dispense loop or wafer line. For these reasons, qualification of Toluene Electronic/EL Grade normally includes additional testing beyond the standard monograph: particle counts at ≥ 0.2 µm, total dissolved metals by inductively coupled plasma mass spectrometry, and sometimes sub-ppb chloride or sulfate by ion chromatography.
During front-end-of-line integration, Toluene Electronic/EL Grade is used as a component in cleaning mixtures or as a direct solvent rinse after wet etching. Metallic contamination introduced at this stage can be driven into the silicon lattice during subsequent furnace operations between 300 °C and 950 °C, producing silicide precipitates or recombination centers. Advanced fabrication facilities therefore define wafer-level metal budgets, often in the range of 1×10¹⁰ to 1×10¹¹ atoms/cm² for total metallic impurities, and electronic-grade solvent specifications are designed to keep the solvent contribution to a small fraction of that budget. A representative solvent lot may report sodium, potassium, iron, chromium, and copper at or below 1 ppb each when analyzed by matrix-matched inductively coupled plasma mass spectrometry. Published data for all possible metal distributions in Toluene Electronic/EL Grade is limited, because supplier internal specifications are frequently adjusted to fab-specific requirements. However, the primary technical distinction from ACS or HPLC material is that these low-ppb metal limits are measured, tightened, and reported rather than left uncontrolled. Non-volatile residue below 1 ppm is also critical because after spin-off or drain drying, a 1 ppm residue can still deposit as an organic film on high-aspect-ratio contacts and trenches, contributing to carbonaceous contamination in later plasma processing. Wafer surfaces after solvent contact are monitored by total reflection X-ray fluorescence or vapor-phase decomposition with inductively coupled plasma mass spectrometry to verify that the solvent has not exceeded the relevant metal budget.
For processes using edge-bead removal in lithography cells, Toluene Electronic/EL Grade is dispensed from pressure canisters or central chemical distribution lines into edge-bead removal nozzles and backside solvent rinse stations. The solvent is applied at spin speeds from 1,000 rpm to 2,500 rpm, where its viscosity of approximately 0.56 mPa·s at 25 °C and surface tension near 28.4 mN/m at 25 °C allow it to dissolve resist edge beads without redepositing polymer onto the wafer surface. Compared with acetone or 2-propanol, toluene has stronger solvency for many novolak-based photoresist edge beads, but its higher boiling point of 110.6 °C requires longer exhaust or drying residence after dispense. Point-of-use filtration with hydrophobic polytetrafluoroethylene or perfluoroalkoxy alkane membranes rated at 0.05 µm or 0.1 µm is common because unfiltered containers can introduce particles that cause comet, streak, or spray defects on coated wafers. The surrounding cleanroom is typically controlled to ISO 14644-1:2015 Class 3 or better for defocused solvent handling, and the solvent headspace is maintained under inert gas blanketing. Water absorption can exceed specification in humid fabrication environments; when relative humidity rises above 60%, point-of-use dry gas pressure and sealed dispense connections are required to prevent resist precipitate and edge-bead removal non-uniformity. Toluene Electronic/EL Grade is not a drop-in replacement for propylene glycol methyl ether acetate or other lower-toxicity resist solvents in every system; the replacement decision must account for dispense-pump elastomer compatibility, wafer-contact materials, and downstream exhaust abatement capacity.
Once a container is opened, Toluene Electronic/EL Grade is susceptible to moisture uptake if the headspace is not kept dry and inert. High-volume dispense systems use electropolished 316L stainless steel pressure vessels with polytetrafluoroethylene gaskets, holding the solvent under filtered nitrogen pressure of 0.2–0.4 MPa. Low-volume manual applications may use fluoropolymer or glass containers inside ventilated chemical cabinets. The flash point of toluene is 4.4 °C closed cup, and the flammable range in air is 1.1 vol% to 7.1 vol%. Storage meets Class I Division 2 electrical classification requirements, and transfer equipment is bonded and grounded according to NFPA 30. Storage temperature is usually maintained between 15 °C and 25 °C away from strong oxidizers, acids, and ignition sources. Toluene Electronic/EL Grade should not be exposed to oxygen-permeable hoses for extended periods because headspace oxygen can support slow oxidation reactions, although toluene is not routinely stabilized with peroxide-inhibitor systems. The material is incompatible with strong oxidizing agents such as concentrated nitric acid, permanganates, or dichromates; mixing with these agents may cause fire or decomposition. It is also incompatible with strong bases in the presence of heat and with some fluorinating agents.
Under the European CLP system, Regulation (EC) No 1272/2008 classifies toluene as Flammable Liquid Category 2 with hazard statement H225; Aspiration Hazard Category 1 with H304; Reproductive Toxicity Category 2 with H361d; Specific Target Organ Toxicity–Repeated Exposure Category 2 with H373; Skin Irritation Category 2 with H315; and Specific Target Organ Toxicity–Single Exposure Category 3 with H336. These hazards require closed-loop handling, local exhaust ventilation, and personal exposure monitoring in wafer-fab subfab and lithography service aisles. Elastomer compatibility is another operational boundary: dispense-pump seals and O-rings in aromatic solvent service are selected from perfluoroelastomer or polytetrafluoroethylene materials, whereas nitrile, ethylene propylene diene monomer, and silicone elastomers can swell or leach. Toluene Electronic/EL Grade is therefore qualified as a complete wet-process chemical system that includes container metallurgy, point-of-use filtration, dispense hardware, and analytical release limits rather than as a solvent defined by a single purity number.
