Putty powder is a kind of building decoration material, the main component is talcum powder and glue. Generally, the whiteness of the putty is above 90 and the fineness is above 330. Putty is a kind of substrate used for wall repair and leveling, which lays a good foundation for the next decoration (brushing and painting wallpaper).
The putty is divided into two types: the inner wall and the outer wall. The outer wall putty should resist the wind and the sun, so the glue is large, the strength is high, and the environmental protection index is slightly lower.
The cause of foaming of putty powder：
1. The base layer is too rough and has small holes. The putty compresses the air in the hole during the scraping, and then the air pressure rebounds to form a bubble.
2. The single-pass batch scraping is too thick, and the air in the pores of the putty is not pressed out.
3. The base layer is too dry, the water absorption rate is too high, and it is easy to cause more foam on the surface layer.
4. Water-resistant paint, high-grade concrete and other airtight surfaces are not breathable and cause foaming.
5. Putty is easy to generate bubbles during high temperature construction.
Treatment：
1. For the rough surface of the base surface, first add white cement or caulking gypsum to fill the compaction and then scrape the whole batch;
2. The thickness of the surface putty should be about 1mm;
3. The substrate that is too dry can be wetted with water and then putty putty;
4. Use the interface agent to seal the bottom or clean the water to wet the wall.
5. The water absorption of the substrate is too low.
- When the putty batch is scraped, the relative water retention time is too long, so that the putty is in the slurry state for a long time without drying, so that the bubbles are not easily squeezed out by the trowel!
- The occurrence of pinhole-like pores is the reason why the top of the scraping template is more than the air bubbles in the wall.
- The water absorption of the wall is large, and the water absorption of the top of the template is extremely low!
6. The amount of cellulose added is too large!