Issue #24 - What are Synthetic Rubber Conformal Coatings & Their Advantages?

February 23, 2017

What are Synthetic Rubber Conformal Coatings & Their Advantages? 

by Marie Kaing - HumiSeal

As the pitch density and packing density of electronics continues to miniaturize as a function of form factor and increased functionality, the requirements posed upon conformal coatings are changing. Increased operating temperature requirements along with an increase in long-term assembly reliability demands are becoming more prevalent. As a result, HumiSeal has introduced a range of synthetic rubber products that exhibit superior performance in these challenging conditions.

Synthetic rubber materials are unique conformal coating products that enable users to achieve superior protection of electronic assemblies especially in high temperature and harsh environments. They exhibit excellent moisture protection, superior mechanical properties, higher continuous operating temperatures and improved no-clean compatibility compared to traditional type materials.

Synthetic rubber copolymers contain specifically formulated blocked alkenes. These materials are extremely flexible and yielding under various temperatures, additionally they offer superior moisture protection. This translates to greater reliability testing performance as the material “flexes” and “recovers” under various stresses during thermal shock and thermal excursion testing.

Material performance and process advantages:

• Higher operating temperature range provides improved performance over standard coatings to address high temperature operating environments

• Excellent moisture protection due to low moisture vapor permeability (MVP) reduces the potential for dendritic growth

• Excellent adhesion to various type of substrates gives user wider application window

• Reduced production and/or delivery errors

• Versatile application methods (selective, dipping, spraying, brushing) allow for more cost-efficient equipment selection and investment

• Fast drying by solvent evaporation for high throughput during manufacturing

• Increased compatibility with no-clean process compared with traditional technologies

• Easy to rework in case removal is required

• Synthetic rubbers meet the requirements of IPC-CC-830 as well as many automotive OEM standards. They are also UL 94 rated for flammability.