How to address wrinkles after putty application?
Release Time:
2020-07-20
Source:
Crinkling occurs after putty application.
Cracking in the putty after application is caused by rapid solvent (water) evaporation from the surface, leading to linear shrinkage. There are generally three solutions:
1. Slow down the evaporation rate of the surface solvent; if it is
For water-based formulations, consider adding slow-evaporating water-soluble solvents, such as ethylene glycol and propylene glycol.
2. Reduce the dosage of film-forming agents (such as emulsions, resins, latex powders, and adhesives), gradually shifting the film-forming phase in the system from a continuous phase to a dispersed phase, thereby minimizing wrinkling caused by linear surface shrinkage during putty drying.
3. Appropriately match the particle sizes of the powder materials and increase the gradation ratio of the coarse powder, ensuring that the drying rate of the base layer is equal to or greater than that of the top layer, thereby maximizing the uniformity of the putty layer’s drying and minimizing wrinkles caused by linear shrinkage.
Lose followers
1. The base wall is excessively dry, the wind speed is too high, and its water absorption is too strong. As a result, the water-resistant putty cannot hydrate and cure properly after application, leading to surface chalking. First, dampen the surface once with a roller dipped in water.
2. If the construction is carried out in accordance with the construction manual’s standard procedures, this situation will not occur.
Peeling
1. The substrate has insufficient strength, resulting in chalking or flaking, which leads to hollowing and even peeling of the finish putty layer. This is commonly observed when water-resistant putty is applied over ordinary putty layers (containing whitewash powder, double-fly powder, or lime powder) or plasterboard surfaces.
2. The base wall surface has not been properly cleaned, with loose dust or other debris present, preventing the water-resistant putty from adhering properly.
3. Improper curing of the cement leads to form release from the substrate, reducing the adhesion of the cement surface and preventing the water-resistant putty from adhering properly.
Cracking
1. Applying a single coat that is too thick can cause the water-resistant putty to crack during the curing period, resulting in microcracks.
2. Construction under high-temperature conditions, in windy environments, and at low temperatures.
Foaming
1. The cement base has not yet completed its curing period, resulting in excessive alkalinity. This high alkalinity in the water-resistant putty layer during the curing phase leads to blistering after drying.
2. If the base wall is too dry and the putty is applied too quickly, air can become trapped in the putty layer, causing blistering. This issue can be resolved by reapplying the putty several times.
Yellowing
1. Applying putty at the same time as polyester paint or release agent can cause the putty film to yellow.
2. Oil stains or other grease-based contaminants on the substrate were not thoroughly cleaned, resulting in yellowing of the putty film.
3. Contamination of the putty film by rust or other colored substances may cause it to yellow.
4. Temperature too low (below 5°C)
