Tin-Free Curable Resin Composition for Large-Area Bond Curing

The patent removes the harmful organic tin catalyst from the curing system and replaces it with an inorganic catalyst (such as metal oxides or inorganic salts). This extraction of the harmful substance while maintaining the curing function resolves the contradiction between curability and toxicity.

The patent employs inorganic catalysts that are non-toxic and environmentally benign compared to organic tin catalysts. These inorganic alternatives provide the necessary catalytic activity for curing without the harmful side effects, effectively replacing the expensive and toxic organic catalyst with a safer, more sustainable option.

The patent optimizes the type, amount, and combination of inorganic catalysts to achieve the desired balance between toxicity reduction and curability maintenance. By adjusting catalyst parameters (such as using composite catalyst systems or modifying catalyst concentrations), the patent achieves both low toxicity and good curability performance.

The patent employs composite catalyst systems combining multiple inorganic catalysts or catalysts with other functional additives to achieve synergistic effects. This composite approach allows the system to maintain low toxicity while ensuring adequate surface and internal curability that single-catalyst systems cannot achieve alone.

The patent divides the curing process into surface curing and internal curing phases, with the surface layer curing first to form a protective barrier, followed by controlled internal curing. This segmentation allows the resin to achieve bonding capability while managing the time required for internal curing through controlled moisture penetration.

The patent incorporates preliminary measures such as surface treatment, primer application, or moisture barrier layers that facilitate uniform moisture distribution and accelerate internal curing. These preliminary actions prepare the substrate and resin system to achieve complete curing more efficiently, reducing the overall time loss.