Coating knowledge: coating lecture: how to prevent blistering of heavy anti-corrosion paint

Core tip: during the coating process of heavy-duty anticorrosive paint, common problems often occur in the engineering quality, such as undercutting of coating, foaming in some areas, etc the reason for this phenomenon is that in a short period of time after the application of the top coat, the top coat film will automatically expand, shift, shrink, wrinkle, bubbles in some areas, and even make the bottom coat lose adhesion, resulting in undercutting of the lower coat The matching performance of the coating is not good, and the primer and the top coat are not matched The coating with strong polar solvent is applied on the upper layer of the coating made of the less polar solvent For example, nitrocellulose paint is applied on the top of alkyd paint or grease paint; large paint is applied after the resin containing rosin film is formed; alkyd paint is applied on anti-corrosion paint; and Paint knowledge | precautions for wall paint color selection Recommended introduction: when painting the wall, the owner sometimes has difficulty in choosing what color of the wall paint to paint In fact, there is no ugly color in the wall paint, only the disharmonious color matching The use of wall color contains the knowledge of health Too strong color will stimulate people's perception, make people have a sense of fidgety, affect people's mental health Grasp the basic principles of wall color and paint a colorful space 1、 Wall paint color selection notice 1 Light color is generally used for the top surface Light colors make people feel light, dark colors make people feel heavy Usually, the treatment of rooms is from top to bottom, from shallow to deep For example, the ceiling and walls of rooms are white and coating Home news: in the coating process of heavy-duty anticorrosive paint, common problems often occur in the engineering quality, such as undercut of coating, blistering in some areas, etc the reason for this phenomenon is that in a short period of time after the application of the top coat, the top coat film will automatically expand, shift, shrink, wrinkle, bubble in some areas, and even make the bottom coat lose adhesion, resulting in undercoat phenomenon The matching performance of the coating is not good, and the primer and the top coat are not matched The coating with strong polar solvent is applied on the upper layer of the coating made of the less polar solvent For example, nitrocellulose paint shall be applied on the top of alkyd paint or grease paint; large paint shall be applied after the resin containing rosin film is formed; alkyd paint shall be applied on anti-corrosion paint; oxidized rubber paint and polyurethane paint shall be applied on alkyd or grease paint The penetration and swelling of the strong solvent to the paint film make the lower layer of the film bite up Apply the next coat before the coat is dry If the perchloroethylene enamel or varnish is not completely dry, apply a second coating When applying the top coat or the next coat, use an over strong diluent to swell the bottom coat The prevention and control measures are that the anti-corrosion paint should be completely dry, and the best coating interval should be followed, and the shortest coating interval must be achieved During the winter construction, the coating interval can be appropriately extended to ensure that the bottom coating is solid For special types of coating, the coating process of "wet touch wet" can be adopted When the first coating is not dry, an additional layer can be applied immediately to improve the adhesion of the coating Paint in strict accordance with the paint instructions Generally, the same kind of anticorrosive paint can be matched with each other Different types of coatings are matched by the principle of hard and soft under; for example, the primer is a strong solvent coating, and the finish is a weak solvent coating It is not appropriate to apply large paint on the rosin resin paint film If painting is to be done, the filter layer must be polished and brushed After drying, the rough particles on the surface shall be removed with a clean cloth After sanding, the large paint shall be applied For the coating with "undercut" defect, it can no longer play the role of protection and decoration The undercut coating shall be removed Touch up and improve matching If the primer is not completely dry, the finish coat shall be applied after the primer is completely dry In order to prevent biting, the first coating shall be thin, and the second coating shall be applied after thorough drying The coating shall not be too thick at one time, so that the internal solvent cannot volatilize and the drying time can be prolonged The diluent used in the coating of anticorrosive paint shall not exceed 5% of the total amount of paint The variety shall also be fixed in the coating process The diluent with weak polarity shall not be used in the bottom layer The solvent with strong polarity shall be used in the upper layer of paint, such as acetone, esters and aromatic solvent with high boiling point Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,