Causes and treatment methods of foaming and yellowing of putty powder


Release time:

2020-10-19

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Causes and treatment methods of foaming and yellowing of putty powder
 
Putty foaming: bubbles generated during the construction process and after a period of time, the putty surface foaming.
Cause:
1. The substrate is too rough, and the batch speed is too fast;
2. The putty layer of primary construction is too thick, more than 2.0mm;
3, the grass-roots moisture content is too high, while the density is too large or too small. Because it is rich in voids and the putty has high moisture content, it is not breathable, and the air is enclosed in the void cavity, which is not easy to eliminate.
4. After a period of construction, the bursting and foaming on the surface is mainly caused by uneven mixing. The slurry contains powdery particles that are too late to dissolve. After construction, a large amount of water is absorbed and swollen to form bursting.
Solution:
1, a large area of foaming putty surface, with a shovel knife directly pressure to break the small bubble mouth, again with appropriate putty scraping foaming surface layer.
2. Putty is generally stirred evenly, let stand for about 10 minutes, and then use an electric mixer to stir again on the wall.
3. If foaming occurs in the second or last surface layer of construction, a scraper shall be used for pressure bubble breaking treatment before watermark elimination to ensure that no bubbles appear on the putty surface.
4, especially rough wall, the general base material as much as possible to choose coarse putty.
5. In the environment where the wall is too dry or the wind is strong and the light is strong, wet the wall surface with clear water as much as possible first, and scrape the putty layer after the wall has no clear water.
 
Putty powder yellowing: refers to the putty after the completion of construction, soon partial or full yellow.
Cause:
Mainly in the indoor old wall, the old wall putty uses a lot of PVA glue, glue aging decomposition, produce unsaturated acid, unsaturated acid and putty in the calcium ion reaction, generate the corresponding yellow calcium salt.
Solution:
1, with environmental protection glue roll coating twice, completely dry, and then apply scraping interior wall putty;
2, with sealing primer roll coating two, thoroughly dry, and then batch of putty.
3, all the use of paste putty construction, or with plate putty construction.
 

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