Prevention of yellowing of white marble
The following points should be paid attention to in the process of processing and installation to prevent quality problems such as the yellowing of white marble so that white marble can perfectly present the beauty of decoration.
1. Due to the internal composition of marble
The yellowing caused by structure occurs through external conditions. Therefore, as long as the water is effectively prevented from passing through the interior of the stone, the yellowing caused by the composition and structure of the stone will be effectively suppressed.
2. The effective way to prevent water from passing through the interior of the stone is to waterproof the back of the board before the stone is installed.
The early waterproof treatment of the stone slab back was painted with a siloxane/silane penetrating waterproof agent. Facts show that the use of this waterproof agent to paint the back of the board cannot effectively inhibit the occurrence of stone lesions, including yellowing. Permeable waterproofing agent has certain limits.
No matter how good the waterproof agent is, its waterproof performance will gradually decline due to the impact of the environment. This is why after the first application of the waterproof agent, it is necessary to repaint it every certain time to repair the deterioration of its waterproof performance. For this reason, the penetration type waterproof agent is only applicable to the panel surface that can be repainted at any time, such as the front of the floor or the wall panel facing outward.
When the permeable waterproof agent is used at the bottom of the board, the waterproof function of the waterproof agent cannot be monitored. Even if there is a sign that the function of the waterproof agent has declined, we cannot repaint and repair it, and we can only let it deteriorate and finally lose the waterproof function completely. This is the main reason why many projects still cannot avoid stone pathological changes by adopting this floor installation process.
As a result, a kind of waterproof back adhesive for stone materials, which uses cement as the base material and is matched with high molecular polymer lotion, came into being. This kind of waterproof back adhesive is called a two-component waterproof back adhesive.
One component is cement, with other inorganic fillers and a small amount of polymer additives, and the other component is organic polymer lotion. This two-component waterproof adhesive must be mixed on-site. Workers lacking professional knowledge often do not realize the importance of the proportion of two components and do not mix in strict accordance with the specified proportion. Therefore, the quality cannot be fully guaranteed.
In addition, this type of waterproof backing has many brands and uneven quality. If the polymer type in the lotion is improperly selected or the solid content is too low, it is likely that it will not play a waterproof role. This two-component waterproof back adhesive is not suitable for white marble with high iron content or marble with more hidden cracks, because when this waterproof back adhesive is applied, the strong alkaline cement water will immediately enter the cracks or pores of the stone and seep from the board surface, and the yellowing of the board surface may occur soon.
3. Yellowing of white marble caused by external reasons can be prevented through reasonable use and maintenance,
For example, place a fiber carpet at the entrance to remove the sand or other hard particles on the sole of the shoe before entering the marble paving area, so as to reduce the wear of foreign hard particles on the stone surface.
The mop used to clean the floor shall be kept clean, and the water used to mop the floor must be clean. After mopping the floor, the water on the ground shall be wiped clean, dry mops shall be used as much as possible, and wet mops shall be used as little as possible. If possible, it is better to use a marble cleaning solution for maintenance. Floor waxing has been proven to be a maintenance method for marble slabs with more disadvantages than advantages.
On the other hand, most of the wax blocks the ventilation pores of the stone, obstructing the gas channel that the marble normally adjusts with the climate.
Finally, when the accumulated wax layer needs to be removed due to aging and yellowing, a dewaxing agent must be used. The use of the dewaxing agent will seriously affect indoor air quality. Choosing the correct crystal surface agent can make the treated stone surface obtain a layer of the compact bright film without affecting the gas permeability of the stone.
However, during crystal surface treatment, if steel wool is used for polishing, the scattered fine powder of steel wool must be cleaned with a vacuum cleaner. Any fine powder of steel wool left on the ground may become a pollution source for the yellowing board surface.
4. The stone installation practitioners must have a certain professional foundation, understand the causes of the yellowing of stones, have the necessary skills for installing stones, keep the construction environment clean and tidy, and avoid the yellowing of stones caused by installation.
Scientific care of stone materials, avoid the introduction of iron that will make stone yellow from washing water or floor polishing process. Use a high-quality permeable waterproof agent to protect the floor regularly, reducing the time and opportunity for water to contact the stone.
Therefore, effective prevention of the yellowing of white marble should be a comprehensive measure. When there is no effective waterproof treatment for cement floors or walls, the treatment of stone slab back is particularly important. It is the most important step of all measures to select waterproof adhesive with guaranteed quality to waterproof the board back.
Removal of yellowing on the stone slab surface
Once the white marble board is found a yellowing, the first thing to do is to find out the cause of the yellowing. Before turning the suspicion of yellowing to rust, it should be determined that yellowing is not caused by aging wax or other external factors. After excluding factors other than iron, preparations should be made to remove rust.
At present, stone care stores have various brands of iron and yellowing removers. Although no product has disclosed the basic chemical components, most of the iron and yellowing removers on the market are acidic. Due to the poor acid resistance of marble, many acid rust removers also have great corrosion on the board surface while removing rust. Therefore, when using rust remover, remember to stick several layers of toilet paper on the stone surface, and then pour the rust remover on the paper. Wait for about two hours, and the yellow will gradually decrease. After several times, you can remove the yellow.
Professional stone care personnel generally use weak or even neutral acid cleaning agents to minimize damage to the stone. For the stubborn rust spots, the paste method is used, that is, mix the rust remover and diatomite with water to form a paste, then apply the paste on the rust spot, cover it with plastic film and seal the periphery with adhesive tape. After 24h, remove the dry paste and collect the dissolved iron with a special cleaning agent.
This last step is very important, because in the process of rust removal, when iron ions diffuse to the board surface, if these iron ions diffuse to the board surface and are not collected completely, the secondary yellowing will occur quickly, and the area will be wider.
In view of the fact that the rust removal on the stone surface is professional work, it is not recommended that nonprofessional owners or nonprofessional nursing personnel purchase unknown rust removers without authorization to remove the yellow spots or rust spots on the stone, so as to avoid permanent damage to the stone caused by improper use.
