Several concepts of sealant curing performance:
Two-component sealant is carried out by chemical reaction between components A and B. The A and B components are sealed and stored separately. Once the components A and B are mixed, they start to react, so the components A and B should be used immediately after mixing. The two-component curing reaction does not require the participation of moisture in the air, so its curing is carried out simultaneously with the interior and the surface. The complete curing time is independent of the thickness of the glue, so the reaction is not related to whether or not it is in contact with air, as long as A, The components B are mixed together and solidified even in a sealed state.
The following are a few concepts of sealant curing properties:
Dry surface: The sealant is creamy when it is punched out. When it is touched with a finger or other material, the compound will adhere to the finger or material. After the sealant is punched out, the surface contacts the moisture to start to solidify the crust. When the skin is formed, and then the finger or material is used to contact the surface, no glue will adhere to the fingers and the material. This is called the stem.
Dry time: When the sealant is shot from the container, the time required for the surface to dry is the dry time.
Detackification: After the sealant dries, touch the surface with your fingers. Although no glue adheres to the finger, you can still feel a certain adhesion between the surface of the glue and the finger. This phenomenon is called No sticky. This is that the curing reaction of the rubber surface has not yet been fully demonstrated. As time goes on, it will cure further until the surface forms a layer of skin with a certain elasticity and strength. It feels dry with finger contact and has no sticky feeling. We call it tack free.
Tack free time: The time required for the sealant to start from the container and the time it takes to tackify the surface is the tack free time.