First, let's focus on the reaction mechanism of the platinum catalytic system, that is, the addition type. All addition-type release coatings contain three basic components, namely the main agent, the crosslinking agent and the platinum catalyst. More strictly speaking, there should actually be four components, and there is an inhibitor, which is usually added to the main agent. There are many types of inhibitors. In China, the most common one is ECH. Generally speaking, the flash point of inhibitors is low and they will volatilize at more than 70 degrees, so inhibitors are rarely added to the client, unless in extremely special application scenarios, so there will be no pollution problems. In addition to these three (or four) main components, various additives are sometimes used, such as heavy peeling control agents, adhesion promoters, etc. The use of additives depends on the formula of the specific application and needs to be determined according to the actual situation.


Next, the chemical structure of each component and its role in the formula are briefly explained.


The main agent is the largest component in the release coatings. The commonly used main agent in the release coating is a low-viscosity terminal vinyl silicone oil, and its most commonly used viscosity range is between 300cs and 500cs. Since the release coating formula is mainly determined by the main agent, it has an important influence on the release force and release force curve of the release coating, and is also related to the stability and reactivity of the coating, and will also affect the curing speed, bath life, adhesion and spreadability.


Crosslinking agent, in simple terms, is hydrogen-containing silicone oil. The effect of crosslinking agent on the function of the formula should not be underestimated, such as release force, reaction speed and adhesion performance. Among them, reaction speed and adhesion performance are the key manifestations of the crosslinking agent.


The catalyst has a relatively small effect on the release coating after the formula is cured. Its main role is to affect the bath life of the release coating ormula, the reaction speed of the formula and the stability.