Curing

What is Curing?

The chemical process by which platinum-cure silicone hardens and cross-links after its two liquid components (Part A and Part B) are mixed together.

What Is the Chemistry Behind Curing?

Curing is the irreversible chemical reaction that transforms liquid platinum-cure silicone into a solid, flexible, body-safe elastomer. The process begins the moment Part A (the silicone base) and Part B (the platinum catalyst) are combined. The platinum catalyst initiates a cross-linking reaction where individual polymer chains bond together into a dense three-dimensional network. Unlike drying — where a substance simply loses moisture — curing is a true chemical transformation. Once cured, the silicone cannot be returned to its liquid state. The cross-linked molecular structure is what gives finished silicone its remarkable combination of flexibility, durability, and non-porous safety.

What Are the Cure Stages and Timing?

Silicone curing happens in two distinct phases. The first is demolding cure, which typically takes 4 to 6 hours at room temperature. At this point the silicone has solidified enough to be removed from the mold without deforming, but the cross-linking reaction is still ongoing internally. The second phase is full cure, which requires an additional 24 to 72 hours depending on formulation and ambient conditions. Only after full cure does the silicone reach its rated Shore hardness, achieve maximum tear strength, and become completely safe for body contact. Reputable makers always allow full cure time before shipping — rushing this step results in a toy that feels slightly tacky, smells of uncured chemicals, and has not reached its final physical properties.

What Factors Affect Cure Time?

Temperature is the single biggest variable. Heat accelerates the platinum-catalyzed reaction dramatically — many professional makers use heated cure ovens set to 150-175F to reduce demolding time from hours to under 60 minutes. Conversely, cold environments slow curing significantly. Catalyst ratio also matters: increasing the Part B percentage speeds up the cure but can make the silicone slightly more brittle. Contamination is the most dangerous variable. Sulfur, tin, latex, and certain modeling clays can completely inhibit the platinum catalyst, resulting in silicone that never fully cures — a costly and frustrating outcome known as cure inhibition. This is why makers keep their workspaces meticulously clean and never use sulfur-based clay near their mold making operations.

Why Does Curing Matter to Buyers?

Understanding curing helps you make better purchasing decisions. A toy that arrives slightly tacky or has a chemical smell may not have been fully cured before shipping — contact the seller immediately. Properly cured platinum silicone is odorless, non-tacky, and dimensionally stable. It will not shrink, warp, or degrade over time with proper care. When browsing the LustMonster catalog, every piece has undergone complete curing and quality inspection before it reaches your door. The patience required in the curing process is one reason turn around times in the fantasy toy industry run longer than mass-produced alternatives — and why the end result is worth the wait.