Mixing Degassing and Room Cure Control for Pad Printing Silicone Heads Hongye Silicone

The pad head sets its quality at the mixing bench. Part A should be checked for settling and stirred before weighing. The catalyst is weighed by scale at 100:2~100:3; guessing the ratio leads to uneven cure and sticky spots. Once added, stir in one direction for 2 to 3 minutes until the two parts are uniform, with no dry streaks left in the bucket.

Why Degassing Matters

Mixing drags air into the compound. Trapped bubbles show up as pinholes, pits and skin peeling after the head starts pressing. Vacuum degassing runs 3 to 5 minutes while surface bubbles clear. Overlong vacuum makes the compound crosslink early and thin out the pouring flow. In small batches without a vacuum pump, reduce the catalyst slightly and pour from a higher point so the stream releases air on its own.

Curing Under Room Conditions

Condensation grade silicone cures with air moisture and catalyst in 3 to 4 hours at room temperature. Cold air slows the reaction, and dry air can leave a tacky interior under a dry skin. Keep the mold still while setting; do not flip or tap it. Below 5 degrees the reaction can stall, so move the work to a warmer room.

Finishing and Long Term Care

Demold and inspect for bubbles, cracks and shade variation, trim flash before mounting. A sound head runs clean, rebounds evenly, and picks up and releases ink steadily. Store heads flat without compression, and clean the ink regularly to keep impurities off the surface. Each raw batch is checked for viscosity, hardness, tensile and tear before dispatch.