Metope requirement: : metope must dry, have carrying capacity, have absorb water ability, clean, PH value neuter and smooth.
A). Dry wall
Observe the base surface color by the eye and judge whether the wall is completely dry.
Film test: cover the wall with a plastic film and cover the sides with tape. If the wall is not completely dry, the remaining moisture in the wall will appear on the back of the film as condensed water. In this case, it cannot be immediately constructed, and must wait for the moisture to evaporate and then paste.
B). Load capacity
Use a hard object to scratch the wall of the experiment, to measure the strength of the wall.
2.Under certain pressure, the wall of the wall was scratched and not cracked.
3. Use the thumb nail to do the stress experiment. If there is no indentation left in the test site, the wall should be strong enough to be pasted.
C). Detection of ph
The wall that usually requires wallpaper construction should be in a neutral state (PH = 7).
When checking the alkalinity of the wall, use distilled water to wet the wall and place a test paper. If the PH is around 7, it's neutral, and the color is olive green. If the walls are alkaline, the yellow test strips will become blue, which means the PH is more than 8. The results can be obtained by comparing with the color palette.
D).Wall absorbing water
Metope absorbs water too high or too low to stick wallpaper is unfavorable.
The method that examines water absorbing ability is wet water law: sprinkle water on metope, the metope water that does not absorb water can become bead flow, this kind of metope must undertake polishing; If the water absorbing ability is very high, the metope can absorb water quickly and color immediately becomes deep, such metope also needs to be dealt with again.
E). Clean one.
1.No dirt, dirt, dirt, etc. 2. Thin material wallpaper and pure white wallpaper request metope color agree.