Gypsum putty is also known as wall scraping putty, a powdery material with building gypsum powder and talcum powder as main materials, mixed with a small amount of gypsum modifier. When using it, add water to stir evenly and level the wall by blade coating. It is the ideal base material for spraying coating and pasting wallpaper. If gypsum powder of high fineness is selected or inorganic pigment is added, it will then be directly used as interior decorative finishes.
As well all know, decoration on the surface of concrete walls and roof should go through such processes as surface course plastering and then applying putty after degreasing, chiseling and plastering screed mortar, both time consuming and labor consuming, with more ash to the floor, and difficult to guarantee no hollowing or cracking phenomenon. Gypsum putty take full advantages of the features of building gypsum, including quick setting, high bonding strength and being white and delicate. And it is prepared with the addition of various admixtures for improving gypsum performance, a thin-layer plastering material in a broad sense. For gypsum putty of this kind, the comprehensive strength is greater than 4.0MPa, the flexural strength greater than 2.0MPa, the bonding strength greater than 0.3M Pa, and the softening coefficient between 0.3 and 0.4, so collapse phenomenon will not occur after water absorption of this hardened paste. However, the hardened paste of traditional putty from talcum powder and calcium carbonate powder relies entirely on the drying intensity. After immersion in water, immediately it will collapse.
In recent years, there have also been such products in the market as waterproof putty and paste putty, whose prices are more than a thousand yuan per ton, making some civilian residential consumers scared off. Therefore, the real gypsum putty is an indispensible material for civilian and public buildings at the present stage. The traditional gypsum putty is mostly used by mixing talcum powder, calcium carbonate powder, sodium alginate or cellulose ethers, and white latex into thick paste at the construction site. With this approach of leveling walls, the quality cannot be guaranteed. Peeling, shedding and dusting phenomena cannot be avoided, not to mention pasting wallpaper on top of it.