Color coating board corrosion prevention

What coating can do finish coat color besmear board is used after period of time, because be affected by all sorts of environmental factors, its besmear film property and service life can reduce, need to undertake repaint to its.The most basic requirements for the repainted coating is to have a certain degree of adhesion with the original coating, and a better durability.Outdoor color coated board according to the use of the environment can be divided into three categories, the first category, the use in the natural environment, the requirements of a certain anti-corrosion effect.Such as: the construction site, using color coated board isolation;Class 2, used in the natural environment, has a certain corrosion prevention and appearance effect.Such as: in the outdoor construction of mobile board house;The third category, used in some harsh environments, requires a certain number of anti-corrosion life.

Adhesive force on different color coated plates to determine the coating system for color coated plates.Polyester amino system coating surface contains a large number of hydroxyl and amino groups, and the building color coating plate is mostly semi-optical coating, coating contains a large number of fillers or matting powder, the micro surface presents a certain roughness, easy and repair coating on the group hydrogen bonding and doxtail wedge effect, so the adhesion is strong.

According to the surface wetting theory, the surface tension of the selected repair coating must be lower than the surface tension of the color topcoat for wetting;Repair coatings should contain polar groups that can form hydrogen bonds;Repair paint to contain strong solvent can be swelling paint, in order to improve the adhesion between layers;At the same time, the coating can be used to lower the relative molecular weight of the resin or reduce the viscosity of the coating, the use of slow volatile solvent and lower cross-linking rate of the coating to improve its adhesion on the color coating plate.