Silicone-to-Plastic
Overmolding
Engineered multi-material integration -- bonding food-grade silicone with PP, PC, ABS and other engineering plastics. Precision tooling, verified adhesion, and consistent mass production for global brands.
Engineered for all
major plastic substrates
We select the right silicone grade and bonding method based on the substrate's surface energy, thermal tolerance, and end-use environment -- ensuring durable adhesion across diverse engineering plastics.
Low-cost · Chemical resistant
Low surface energy requires plasma treatment or specialized primers. Ideal for kitchenware, food containers, and household items.
- Plasma surface activation
- Primer-assisted bonding
- Food-contact certified
High-strength · Transparent
Excellent impact resistance and heat tolerance. Suitable for baby products, premium drinkware, and transparent housings.
- Direct chemical bonding
- High heat deflection
- BPA-free grades available
Rigid · Easy to process
Strong mechanical properties and excellent surface finish. Widely used in consumer electronics, appliances, and toys.
- Reliable primer bonding
- Smooth surface finish
- Paintable & printable
Chemical bond +
mechanical interlock
True overmolding reliability comes from two forces working together -- molecular adhesion at the interface, and geometric interlock engineered into the plastic substrate.
Chemical Adhesion
Primer coatings, self-bonding LSR, and plasma surface activation form molecular-level bonds exceeding 2.0 N/mm peel strength.
Mechanical Interlock
Undercuts, through-holes, grooves and dovetail features designed in DFM stage lock silicone physically to the plastic.
DFM Collaboration
Our engineers co-design the plastic substrate for optimal silicone flow, venting, and bond-line durability.
Precision tooling,
controlled molding flow
Every overmolded part begins with precise insert positioning, custom-engineered tooling, and tightly controlled injection parameters. Our 64 production lines are configured for both insert-molding and two-shot workflows.
Substrate molding & surface treatment
Plastic inserts are injection-molded, inspected for dimensional stability, then plasma-treated or primer-coated to prepare the bonding surface.
Insert positioning & tool engineering
Custom tooling with precision locating pins holds plastic inserts within ±0.05mm. Gate placement, venting and runner balance are optimized via mold-flow simulation.
Overmolding & curing
LSR or HTV silicone is injected around the positioned insert under controlled temperature, pressure, and cure cycle -- ensuring complete fill without substrate deformation.
Deflashing, inspection & finishing
Parts are deflashed, dimensionally inspected, and finished with silkscreen, UV coating or laser marking as specified -- ready for assembly or packaging.
Three dimensions of
overmolding excellence
Durable adhesion, dimensional stability, and flawless surface finish -- managed through engineering controls, in-process monitoring, and final-stage verification.
Adhesion Control
Verified bond strength through pull tests, 180° peel tests, and cross-cut adhesion checks. Primer compatibility pre-validated for each substrate.
- Peel strength > 2.0 N/mm
- Pull-off test Cohesive failure
- Thermal cycling -40 to 200°C
Deformation Control
Controlled injection temperature, pressure, and cycle time prevent substrate warping. Mold-flow simulation validates thermal balance before tooling cuts.
- Tolerance ±0.1 mm
- Warpage < 0.3%
- Shrinkage comp. Mold-flow verified
Appearance Control
Clean bond lines, consistent surface texture, color-matched finishes. Zero visible flash, no bubbles, uniform matte or glossy appearance per spec.
- Bond-line Clean, flash-free
- Color matching Pantone / RAL
- Surface finish SPI A1-D3
Overmolded products
across industries
From kitchen tools to baby products -- proven in global markets.
Soft-grip utensils
PP/Nylon handles overmolded with food-grade silicone grips. Heat-resistant to 230°C.
Feeding & teething
PC/PP base with LSR silicone overlay. FDA, LFGB certified. BPA-free throughout.
Collapsible cups
PP rim overmolded with food-grade silicone body. Fold-flat, leak-proof design.
Ergonomic grips
ABS housings with soft-touch silicone overmolded zones for improved user comfort.
Non-slip pet bowls
PP/ABS bowl structure with silicone anti-slip base. Dishwasher safe.
Seals & gaskets
High-temp HTV silicone over PA/PBT inserts. Custom shore hardness 30-80A.
Verified testing.
ISO 9001 production.
Every overmolded part passes a structured testing protocol -- from first-article inspection through batch sampling and 100% final visual checks. Full traceability from raw material to finished goods.
Peel & Pull Test
180° peel & direct pull per ISO 813, verifying cohesive failure mode.
Thermal Cycling
-40°C to +200°C cycling to validate long-term bond integrity.
Chemical Resistance
Immersion testing against detergents, oils, acids & alcohols.
Aging & UV
Accelerated aging & UV exposure to confirm long-term durability.
First Article Inspection
Full FAI report before mass production approval sign-off.
AQL Batch Sampling
AQL 1.5/2.5 sampling with SOP-driven in-line inspection.
Upload your structure files for a
free overmolding assessment
Share your 3D files, drawings or sketches. Our engineering team will respond within 24 hours with substrate compatibility analysis, bonding recommendations, and a tooling & production proposal.
- Supported: STEP, IGES, STL, DWG, PDF, JPG, PNG
- NDA available upon request
- Response within 24 hours