polyurethane topcoat and curing agent ratio should be how?

polyurethane topcoat is a two-component polyurethane anticorrosive topcoat composed of synthetic resin as base material, coloring pigment and curing agent.

polyurethane topcoat refers to the paint film containing urethane bond coatings, there are one-component and two-component varieties, one-component is now rarely used (that is, use only as a primer), commonly used in steel structure surface coating is a two-component polyurethane topcoat, one component is hydroxyl-containing resin component, the other component is isocyanate-based resin component.

Polyurethane Resin Coating for Steel Structure

key points to focus on the following factors:

1. Solids

is divided into volume solids and weight solids, which represent the active ingredients of the paint. Especially volume solids. According to the volume solids and specific gravity, the theoretical weight of paint under a certain dry film thickness can be calculated, supplemented by the price of kilograms, the theoretical cost can be calculated.

solids can be divided into the factory state and the construction state. In the case of the same factory state solids, the lower the viscosity of the paint, the less diluent may need to be added during construction, which can save the cost of diluent and reduce VOC emission pollution. That is, high solid and low viscosity type, which is the development direction of polyurethane topcoat.

2, weather resistance

is the polyurethane topcoat's ability to preserve light and color. This ability is related to the hydroxyl group, isocyanate group, pigment and additive of polyurethane topcoat. The standard for testing weather resistance includes accelerated light aging test and exposure test under natural weather conditions. Usually this indicator is difficult for users and the cost of testing is high.