E962 Class B Air-Drying Insulating Varnish for Coils & PCBs

Description

Product Overview：

E962 is an electrical insulating varnish for surface coating and impregnation of electrical and electronic components. Its modified polyester formulation produces a transparent, pale yellow coating and offers a choice of air drying or oven drying to suit different production requirements.

This Class B insulating varnish is intended for applications requiring a thermal class of 130°C. It is suitable for protecting circuit boards and insulating coils, transformers, and motor windings where coating performance and processing flexibility are important.

E962 provides a specified dielectric strength of ≥40 kV/mm under normal conditions and ≥30 kV/mm after the stated 24-hour water immersion test. These properties support its use in applications requiring electrical insulation and resistance to moisture exposure.

The TDS also identifies E962 as a varnish that does not inhibit soldering. Compatibility with the intended soldering process, coating thickness, and assembly materials should be verified during application trials.

Key Features and Benefits：

  · Air-Drying Capability: Reaches surface dryness in 10–15 minutes at 25°C under the reported laboratory conditions, providing an ambient-drying option for suitable components.

  · Optional Oven Drying: At 80°C, the specified surface-dry time is 5–10 minutes, with through-drying in 75 minutes, allowing manufacturers to select a drying process suited to their production needs.

  · Class B Heat Resistance: Rated Class B, 130°C, in the TDS. Suitability for finished equipment depends on the complete insulation system and operating conditions.

  · Electrical Insulation Performance: Specified dielectric strength is ≥40 kV/mm under normal conditions, supporting insulation of coated or impregnated components.

  · Performance After Water Immersion: Maintains dielectric strength of ≥30 kV/mm and volume resistivity of ≥1 × 10¹³ Ω·cm after the respective 24-hour water immersion tests.

  · Soldering Compatibility: Described in the TDS as not inhibiting soldering, making it relevant to electronic assembly applications where soldering compatibility is required.

  · Transparent Appearance: The pale yellow transparent varnish allows the underlying component surface to remain visible.

  · Application Viscosity Adjustment: The specified X-7 series thinner allows viscosity adjustment according to component geometry and coating or impregnation requirements.

Typical Applications：

E962 insulating varnish is suitable for surface coating or impregnation in the following applications:

  · Printed Circuit Boards: Protective coating of circuit boards and applicable electronic assemblies.

  · Inductor Coils: Electrical insulation treatment of coil assemblies.

  · Transformers: Coating or impregnation of transformer coils and associated insulating components.

  · Small and Medium-Sized Electric Motors: Insulation treatment of motor windings and suitable electrical parts.

  · Other Electrical and Electronic Components: Applications requiring a transparent, air-drying polyester insulating varnish.

Verify compatibility with substrates, wire enamel, plastics, and other assembly materials before production use.

Physical Properties：

Technical Notes:

  · Viscosity is expressed as cup flow time in seconds.

  · Specific gravity is dimensionless.

  · Surface dryness does not indicate complete drying throughout the coating or winding assembly.

  · The Class B thermal rating is distinct from the recommended processing temperature. The TDS recommends that oven-drying temperatures should not exceed 100°C.

Application Guidance:

  · Preparation and Thinning

Use the specified X-7 series thinner when viscosity adjustment is required. Determine the dilution ratio through trials based on the component’s shape, size, coating requirements, and application method.

Confirm compatibility with the actual substrates and assembly materials before applying E962 electrical insulating varnish in production.

  · Coating and Impregnation

Apply E962 by a suitable surface-coating or impregnation process for the component. Establish application parameters through trials to achieve the required coverage and insulation performance.

For PCB applications, verify soldering compatibility using the actual coating thickness, soldering conditions, and assembly sequence.

  · Drying Conditions

These times are laboratory reference values. Actual drying depends on film thickness, component geometry, solvent retention, airflow, and oven loading.

The TDS recommends keeping the oven temperature at or below 100°C. Determine the final drying schedule through trials on the actual component, particularly for impregnated windings where solvent removal may take longer than for a thin surface coating.

  · Humidity Considerations

E962 may absorb moisture and develop a whitish appearance when applied under high-humidity conditions. The TDS states that performance is not affected after baking. Control application humidity and verify the appearance and drying condition before accepting finished components.

Precautions:

  · Determine the dilution ratio, baking temperature, and baking time experimentally based on product shape, size, and specific requirements. Recommended baking temperature: do not exceed 100°C.

  · The product may absorb moisture and turn whitish under high humidity; performance remains unaffected after baking.

  · This product is flammable; keep away from fire and heat sources.

Packaging, Storage/Transport & Shelf Life：

  · Packaging: metal pails, 18 KG/pail

  · Storage & transport: flammable chemical — keep away from fire and heat; handle per regulations; store cool (RT), dark and dry.

  · Shelf life: stored sealed, 6 months at 5-25℃.