| HS Code | 789601 |
| Thermal Conductivity | 1.5 W/m·K |
| Dielectric Strength | 20 kV/mm |
| Volume Resistivity | 10^14 Ω·cm |
| Insulation Class | Class H (180°C) |
| Operating Temperature Range | -50°C to +200°C |
| Adhesion Strength | Grade 1 per ASTM D3359 |
| Viscosity | 5000–10000 mPa·s at 25°C |
| Cure Time | 30 min at 120°C |
| Specific Gravity | 1.45 g/cm³ |
| Coefficient Of Thermal Expansion | 60 ppm/°C |
| Flash Point | 120°C |
| Shelf Life | 12 months in sealed container |
As an accredited Thermal Conductive Insulation Coating Material Electronic/EL Grade factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Packaged in sealed containers with desiccant, 1 kg per unit, for electronic/EL grade thermal conductive insulation coating. |
| Container Loading (20′ FCL) | 20' FCL: palletized drums/cartons, securely braced, weight optimized for thermal conductive electronic-grade coating material transport. |
| Shipping | This electronic/EL-grade thermal conductive insulation coating ships in sealed, moisture-resistant containers with anti-static cushioning. It must be transported at ambient temperature, away from heat, sparks, or direct sunlight. Hazard classification depends on formulation; if solvent-based, label as flammable and follow applicable dangerous goods regulations. Ensure secure upright packaging to prevent leakage during transit. |
| Storage | Store in a cool, dry, well-ventilated area away from direct sunlight, heat sources, and ignition sources. Keep containers tightly sealed to prevent moisture contamination and solvent evaporation. Avoid contact with strong oxidizers and incompatible materials. Follow manufacturer’s shelf-life guidance, and inspect regularly for leakage or degradation. |
| Shelf Life | Shelf life is typically 12 months from manufacture date when stored sealed, cool, and dry in original container. |
In cell-to-pack battery architectures, the thermal conductive insulation coating is applied to laser-welded 3003 aluminum busbars, cold-plate interfaces, and module side plates where polymer film and ceramic tile systems create stack height deviations above 0.25 mm. The two-component formulation is metered at 100:12 by weight through gear pumps; off-ratio excursions beyond ±2% are rejected by the dispenser controller because hardener deficiency leaves residual uncured resin at the aluminum oxide boundary. Pre-treatment consists of oxygen plasma at 80–100 W for 30–45 s, followed by substrate preheating to 45±3 °C. Air-assisted spray at fluid pressure 0.50–0.65 MPa and atomization air 0.15 MPa deposits a wet film of 150–180 µm in two crosses, yielding a dry film thickness of 100–120 µm after solvent flash at 60 °C for 5 min and staged cure at 80 °C for 30 min and 120 °C for 20 min. For cell-to-pack designs, the relevant electrical safety path is evaluated under UL 746E and IEC 60664-1, with a dielectric withstand target of 2.5 kV AC for 60 s and a pinhole-free requirement at 1.5 kV continuous DC. Thermal dissipation is characterized by ASTM D5470-17, and the coating must maintain through-plane thermal conductivity above 1.2 W/m·K after 1000 h at 85 °C/85% RH. Ionic cleanliness is limited to 10 µg/cm² NaCl equivalent under IPC-TM-650 2.3.25. The terminal product is a module-level insulation system in lithium-ion battery packs for electric buses and grid storage cabinets, where busbar pitch is reduced from 12 mm to 6 mm without introducing partial discharge during fast-charge voltage transients of 800 V.
| Property | Test method | Acceptance limit |
| Dielectric strength | ASTM D149-20 | ≥ 18 kV/mm at 100 µm dry film |
| Volume resistivity | ASTM D257-14 | ≥ 1×10¹² Ω·cm after 85 °C/85% RH, 1000 h |
| Adhesion to aluminum | ASTM D3359-17 | ≥ class 4B after thermal shock |
| Flammability | UL 94 | V-0 at 0.75 mm |
| Ionic contamination | IPC-TM-650 2.3.25 | ≤ 10 µg/cm² NaCl equivalent |
Metallic substrates eliminate vapor-chamber thermal resistance but require a continuous dielectric layer with sufficient filler packing to pass IPC-TM-650 2.5.7.2 dielectric breakdown verification after copper etching. For 100 µm dry film, an alumina/boron nitride hybrid filler is held at 45–55 vol% with a bimodal size distribution of 0.3 µm and 3.0 µm particles at a mass ratio of 1:3; this loading raises thermal conductivity to 1.8–2.2 W/m·K under ASTM D5470-17 while retaining viscosity suitable for screen printing at 35–45 Pa·s. The paste is printed through a 77T polyester mesh at a squeegee pressure of 70 N, a squeegee angle of 60°, and a flood stroke speed of 80 mm/s. Wet film thickness is 85–100 µm, which after a 5 min leveling period and 60 °C solvent flash yields the target dry thickness at a wet-to-dry reduction ratio of 1.4:1. Thermal cure at 150 °C for 60 min is followed by a post-etch adhesion check under ASTM D3359-17. For LED modules designed to UL 8750, the dielectric layer must survive 260 °C solder float for 10 s without delamination, and the whole aluminum-core laminate is evaluated under UL 796. Typical terminal products include sealed LED street-lamp engines and automotive headlamp modules operating at junction temperatures approaching 125 °C, where the dielectric layer remains below its glass transition temperature and does not crack during thermal cycling from -40 °C to 125 °C.
For electroluminescent panels, the dielectric layer is printed between the phosphor layer and the rear carbon electrode, not primarily for bulk heat spreading but to stop silver migration and damp dielectric heating at typical AC drive frequencies of 400 Hz to 1 kHz. The paste contains barium titanate filler at 60–70 wt% in a solvent-borne resin system, giving a dielectric constant sufficiently high that the dielectric-to-phosphor thickness ratio can be kept at 1.5:1 to 2.0:1 without lowering luminous output below 35 cd/m² at 110 V AC. Screen printing onto ITO-coated polyester uses a 100 mesh stainless-steel screen, a wet coat thickness of 40–50 µm, and forced-air drying at 120 °C for 10 min. The dielectric layer is evaluated for pinhole density under ASTM D149-20 after bending around a 3 mm mandrel; acceptable panels show no dielectric breakdown below 1.5 kV after 10,000 flex cycles. Moisture resistance is verified by 85 °C/85% RH aging for 240 h followed by 1 kHz drive at 90% relative humidity, a condition that exposes ionic migration through residual unreacted resin. Because the coating is an electronic/EL grade, extractable chloride and sulfate content is controlled below 5 mg/kg each by ion chromatography. Terminal parts are electroluminescent backlights for automotive instrument clusters, wearable safety lighting, and signage panels laminated with 75 µm clear polymer film.
Selective spray application onto toroidal inductors exposes a conflict between overspray control and edge build-up at the wire crossover points. The coating is diluted with a solvent blend at 10–15 wt% of total coat weight, corresponding to a coating-to-solvent ratio of 85:15 to 90:10, to achieve 22–25 s Ford cup 4 viscosity at 25 °C, and atomized with a 0.3 mm nozzle at 0.35 MPa air pressure. The wet film is deposited in three axis rotations, yet Faraday occlusion from tightly wound 0.8 mm magnet wire leaves dry film thickness at the inner windings near 25 µm while the outer rim reaches 75 µm. This thickness gradient is measured with a laser triangulation system and is a known production bottleneck when the minimum dielectric withstand for the coil assembly is 1.2 kV AC for 60 s under UL 1446 insulation system testing. Pot life at 25 °C is 8 h, and viscosity drift beyond +15% triggers automatic purge because the coating no longer penetrates the winding gaps. Cure is performed at 100 °C for 15 min after a 10 min ambient flash, and crosslink density is checked by solvent rub under ASTM D5402-19. Terminal products are toroidal chokes and current transformers in switch-mode power supplies for server racks, where the insulation coating replaces pre-cured polyester tape and reduces winding-to-core capacitance at 100 kHz switching frequency.
IGBT power module baseplates and liquid-cooled heat sinks require a thin isolation coating that maintains partial discharge extinction below 10 pC at 1.5 times the rated working voltage. The material is compounded at a filler-to-resin weight ratio of 65:35 and applied to grit-blasted aluminum with a surface roughness of Ra 2–3 µm. Electrostatic spray deposits a dry film thickness of 175–200 µm for working voltages up to 1.0 kV; the thickness is derived from a design dielectric strength of 18 kV/mm under ASTM D149-20 with a 0.9 derating factor. The single-component material is pre-dried before application when ambient relative humidity exceeds 60%, and cure is carried out at 170 °C for 45 min in a circulating oven. Because the coating replaces compressed thermal pads, contact thermal impedance is measured at 0.35 K·cm²/W under 100 psi clamp load, and the insulation is qualified under IEC 61800-5-1 for adjustable-speed drive safety. A known incompatibility is the combination of alkyd-based air-dry topcoats with the cure chemistry; such systems can inhibit surface cure and lower the comparative tracking index below 600 V when tested under IEC 60112. This configuration appears in industrial motor-drive bricks, solar inverter stacks, and wind converter cabinets where the dielectric layer is sandwiched between the module baseplate and the anodized heat sink without a separate silicone pad.
Roll-to-roll printed heaters demand a low-temperature-cure dielectric that can tolerate elongation after lamination without cracking. The coating is compounded at a resin-to-solvent weight ratio of 70:30 and printed on corona-treated polyester film with surface energy above 52 dyn/cm. A 100 µm wet film deposited by screen printing through a 60 mesh screen yields a 35–40 µm dry dielectric layer after three-zone oven drying at 80 °C, 120 °C, and 150 °C with a total dwell time of 12 min. The dielectric layer is tested after lamination under ASTM D522/D522M-17 for cracking over a 10 mm mandrel, and adhesion to the printed silver ink is checked by tape snap-out after 300 g/25 mm peel force. Compliance for the finished heater assembly typically references IEC 60335-1, while the conductive and dielectric inks are assessed for heavy metal content under RoHS Directive 2011/65/EU and for SVHC under REACH Article 33. The thermal conductivity of this dielectric layer is lower than the MCPCB grade because the filler loading is capped at 30–35 vol% to maintain flex crack resistance; measured through-plane conductivity is 0.6–0.9 W/m·K under ASTM D5470-17. Terminal products are seat heaters, mirror defoggers, and medical warming pads where the dielectric layer separates the carbon heating loop from the outer fabric cover and withstands a 1.5 kV AC dielectric test for 60 s after 500 thermal cycles from -20 °C to 85 °C.
Competitive Thermal Conductive Insulation Coating Material 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!
Thermal Conductive Insulation Coating Material Electronic/EL Grade is supplied as a two-part, alumina-filled epoxy-silicone hybrid under designation EL-TC-2280. The A-component contains a diglycidyl ether of bisphenol A resin modified with a phenyl silicone intermediate; the B-component is a cycloaliphatic amine hardener with a tertiary amine accelerator. Mix ratio is 100:28 by weight. Mixed viscosity at 25 °C is 12,000–18,000 mPa·s when measured with a Brookfield RV viscometer, spindle 6, at 20 rpm, in accordance with ISO 2555:2018. After a 30-minute induction period at 23 °C, viscosity rises to 45,000 mPa·s at 60 minutes, which defines the practical dispensing window for progressive cavity pumps with static mixers. The cured film achieves thermal conductivity of 1.2 W·m⁻¹·K⁻¹ as measured by laser flash method per ASTM E1461-13 and dielectric breakdown strength of 18 kV·mm⁻¹ per IEC 60243-1:2013 on 200 µm dry film. The material contains no intentionally added borosilicate glass or quartz; the filler system is spheroidal alumina with a median particle size of 8 µm and a top cut of 25 µm.
| Property | Test method | Typical qualification value | Unit |
|---|---|---|---|
| Thermal conductivity | ASTM D5470-17 | 1.2 | W·m⁻¹·K⁻¹ |
| Dielectric strength, dry film 200 µm | IEC 60243-1:2013 | 18 | kV·mm⁻¹ |
| Volume resistivity | IEC 62631-3-1:2016 | 2.5 × 10¹⁴ | Ω·cm |
| Surface resistivity | IEC 62631-3-2:2016 | 8.0 × 10¹⁴ | Ω |
| Mixed viscosity | ISO 2555:2018 | 12,000–18,000 | mPa·s |
| Cure schedule | — | 30 min at 80 °C plus 60 min at 120 °C | — |
| Lap shear on Al 6061 | ASTM D1002-10 | 12 | MPa |
| Coefficient of linear expansion below Tg | ISO 11359-2:2021 | 45 | ppm·K⁻¹ |
| Glass-transition temperature by DSC | ISO 11357-2:2020 | 105 | °C |
| Flammability rating | UL 94 | V-0 at 0.4 mm | — |
| Filler median particle size | Laser diffraction | 8 | µm |
The values in the table are derived from qualification lots; they do not constitute a certificate of analysis for any shipment. The product is supplied pre-measured in dual cartridges configured for a 10:1 volume ratio static mixer with 18 mixing elements. Pot life at 25 °C is 45 minutes to double initial mixed viscosity, measured as the time to reach 36,000 mPa·s from the baseline midpoint of 15,000 mPa·s.
For an insulated metal substrate busbar carrying IGBT modules, the continuous operating class is governed by oxidative stability of the silicone-modified epoxy network rather than by the alumina filler. Long-term aging data generated at 150 °C and 175 °C on 150 µm cured films show time to 50% reduction in dielectric strength is 2,800 h at 175 °C under forced-air conditions per IEC 60216-1:2013. Thermal conductivity remains within ±8% of initial value after 1,000 h at 150 °C when measured by ASTM D5470-17. The material is therefore assigned a thermal class of 130 °C for continuous electrical insulation service, with short-term excursions to 180 °C limited to 4 h cumulative. Above 185 °C, the phenyl silicone phase begins to depolymerize, producing cyclic siloxanes and a measurable loss of film flexibility. Field data from insulated busbar production show that edge cracking initiates when cumulative exposure exceeds 72 h at 175 °C, propagating from sharp-formed copper corners at a bend radius below 1.5 mm.
On a high-speed surface-mount assembly line with a selective coating robot equipped with a progressive cavity pump, the EL-grade material is dispensed at 0.6 MPa nozzle pressure through a 0.4 mm needle. Wet film thickness of 250 µm is achieved at 120 mm·s⁻¹ traverse speed. The coating exhibits pseudoplastic flow with a viscosity at 10 s⁻¹ of 9,800 mPa·s and at 100 s⁻¹ of 3,200 mPa·s, which prevents sag on vertical surfaces after 2 minutes at 50 °C. In production lots, batch-to-batch variance of the mixed viscosity has been recorded at ±1,200 mPa·s across 14 consecutive releases; this variance shifts the wet film thickness by ±18 µm under constant nozzle pressure. Process engineers compensate by adjusting nozzle pressure within 0.55–0.70 MPa, not by altering mix ratio, because deviations from the 100:28 ratio beyond ±2 parts by weight lower crosslink density and reduce glass-transition temperature by 8 °C per part deviation. After cure, the coating retains adhesion to FR4 and polyimide with cross-cut class 1 per ISO 2409:2020, provided the substrate surface energy exceeds 38 mN·m⁻¹ measured by contact angle with diiodomethane.
Adsorption of moisture on spheroidal alumina surfaces at relative humidity above 60% leads to a competitive reaction between water and the cycloaliphatic amine. This reaction consumes active hydrogen equivalents and generates a microporous cured film with reduced dielectric strength. Qualification data show that films applied at 70% RH and 23 °C have dielectric breakdown strength of 14.5 kV·mm⁻¹, a reduction of 19% from the 18 kV·mm⁻¹ baseline. The coated substrate must be pre-dried at 60 °C for 30 minutes before dispensing when ambient RH exceeds 60%, and the dispense booth should be held at 35–45% RH. The material is incompatible with tin-free amine accelerators and with phosphite antioxidants at processing temperatures above 40 °C; the latter generate acidic decomposition products that inhibit the tertiary amine. In automated lines with solventless cartridge feed, the outlet of the static mixer must remain capped between shots to limit surface skinning; skin formation as thin as 0.3 mm is sufficient to create inclusion defects that reduce dielectric strength at pinhole-prone copper trace edges by up to 22%.
Differences from silicone thermal gels and polyurethane conformal coatings arise from the cured network architecture. Silicone gel systems offer lower modulus but also lower dielectric strength at comparable thermal filler loading. Polyurethane conformal coatings provide elongation at break above 100% but are limited to thermal conductivity below 0.4 W·m⁻¹·K⁻¹ when unfilled. The EL-grade product is specified where a single material must provide both electrical isolation and lateral heat spreading without the mass of a potting compound. In comparative testing on 2.0 mm thick aluminum-clad IMS substrates, the EL-grade coating reduced hot-spot temperature by 7 °C relative to an unfilled polyurethane conformal coating at the same 200 µm dry film thickness, measured by thermocouple under 2.5 W local dissipation.
| Parameter | EL-TC-2280 | Silicone thermal gel | Polyurethane conformal coating | Epoxy potting compound |
|---|---|---|---|---|
| Thermal conductivity (W·m⁻¹·K⁻¹) | 1.2 per ASTM D5470-17 | 1.0–2.5 vendor dependent | 0.35–0.45 | 0.8–1.0 |
| Dielectric strength (kV·mm⁻¹) | 18 per IEC 60243-1:2013 | 14–16 | 20–24 | 15–18 |
| Mixed viscosity (mPa·s at 25 °C) | 12,000–18,000 | 80,000–250,000 | 200–800 | 3,000–8,000 |
| Pot life (hours) | 1 | No cure | 2–4 | 0.5–1 |
| Adhesion to FR4, cross-cut | Class 1 per ISO 2409:2020 | Not applicable | Class 0 | Class 1 |
In electroluminescent backlighting, the material is applied as a 40–60 µm insulator between the rear electrode and the phosphor layer. At that thickness the capacitance density is 0.8–1.1 nF·cm⁻² at 1 kHz, measured per IEC 60384-1:2021. This value stabilizes the field strength across the phosphor at 1.5 V·µm⁻¹ and prevents local dielectric breakdown at pinholes in the indium tin oxide electrode. The coating must be free of particles larger than 15 µm to avoid forming shorting paths through a 50 µm wet film; the filtration stage downstream of the static mixer uses a 10 µm polypropylene depth filter. For adhesion to palladium-coated silver traces in EL lamps, published data for this specific configuration is limited; qualification is performed on a per-lot basis using ASTM D3359-23 Method B.
High-density interconnect assemblies with 50 µm trace spacing require filtration below 25 µm absolute to prevent single-particle bridging. The product is shipped with a 25 µm absolute filter capsule at the cartridge outlet and a downstream 10 µm depth filter before the dispense valve. Viscosity recovery after filtration is immediate because the formulation is solventless; no solvent flash occurs, and the wet film thickness remains stable within ±10 µm for 8-hour continuous runs. Rework of uncured material is performed with methyl cyclohexane, but cured films require mechanical removal because the silicone-modified network resists swelling in common ketone and ester solvents. Cured film thickness below 30 µm is not recommended for insulation service above 500 V because partial discharge inception voltage under IEC 60664-1:2020 decreases nonlinearly with thickness. The material is not formulated for direct contact with liquid electrolyte systems or for use as a solder mask replacement.
