Natural decorative stone (hereinafter referred to as "stone 1"), as a building decorative material, has the characteristics of bright color and good gloss. In all kinds of buildings in the city, we can see the magnificent landscape created by stone decoration, and at the same time, stone decoration has gradually entered the family, which shows that the stone industry is an industry with great development space. However, pathological pollution of stone is an unavoidable problem. According to the investigation of buildings decorated with stone in Qingdao, it is found that these buildings have been put into use for only three months to six months, and more than 80% of them have different degrees of stone lesions. The occurrence of stone disease not only destroys the beauty of stone, but also leads to engineering disputes in Shi Cun, which further affects people's consumption concept. It can be seen that it is very important to treat the surface with protective agent after processing, so it is imperative to study the protective agent for stone. Research status and progress of 1 stone protectant at home and abroad. Stone maintenance is to brush and protect the stone surface, so that the stone has waterproof, antifouling, antirust, waterproof spots, aging resistance and weathering resistance. At present, the problem of stone protection has attracted the attention of relevant state departments. According to statistics, the utilization rate of protective agents in stone is only 50%, and most of them are imported products. The price is relatively high, about m in 25 yuan, but the domestic products are less than 10 yuan /mm, so the research of stone protectant has broad development space and market prospects. The development of stone protectants abroad has a history of more than 30 years, and the research of stone protectants in Japan, Europe and the United States is in the leading position, and gradually transitions from solvent-based products to water-based products F, that is, environmental protection plough products. In contrast, the research on stone protectants in China started late. At present, relevant standards have not been formulated in China, and most of the protective agents used are imported products from Japan, Europe and America. 1 stone protectant. There are two kinds of stone protectants: coating protectants and penetrating protectants, including: (1) semi-permanent coating, such as wax. The advantage is convenient painting, but the disadvantage is frequent painting: (2) Permanent painting, such as water-soluble organic paint made in Japan, which is composed of 100 parts of polyurethane and 04-40 parts of ethyl butyl ether phosphate, has good water retention, washing resistance and wear resistance. I invented a chain perfluoroolefin polymer phosphate coating, which can play a very good oil-proof and waterproof effect. Italy coated the stone surface with fluoropolyether, which made the stone have good hydrophobicity, weatherability and pollution resistance, and at the same time avoided the color change caused by light interference. Permeable consolidation protectant includes: (1) coating a layer of alkyl fluoride on the surface of granite proposed by Japan, and forming a chemical adsorption film through silicon-oxygen bond to resist the influence of harmful substances in the environment on stone materials and improve the waterproof and pollution-resistant ability. (2) It is mentioned in the European patent that perfluoropolyether can be converted into a derivative with carboxyl or amide groups at the end, which is easy to form a sufficiently stable chemical bond or hydrogen bond with stone, and has good waterproof, oil-proof, flood-proof, acid and alkali resistance and thermal stability, and is also stable to light radiation. (3) A water-soluble inorganic protective agent is put forward in American patent, which is an effective waterproof agent for building materials, and uses a cationic solution of "free salt" silicon dioxide. 1.2 Domestic stone protection agent-Wax protection method is widely used in stone protection in China, but wax protection method is not a reasonable and effective protection method. Because wax is an airtight sealing protection material, when it covers the stone surface. The original pores and fine lines of stone are blocked. Although external water and moisture can't enter the stone, which can prevent pollution to a certain extent, due to the influence of sealing wax, moisture inside and below the stone can't be emitted, so moisture will accumulate in the stone for a long time, which will lead to the pathological changes of the stone. However, if the protection project is to be carried out, the wax on the stone surface is the biggest obstacle for the protective agent to penetrate into the stone, which leads to the protective layer only reaching the surface and unable to carry out the protective function below the stone surface, which may lead to the failure of protection, greatly increasing the risk of subsequent lesions and shortening the life of the stone. 1.3 Comparison of protective performance between penetrant and wax Compared with wax protection, penetrant is not limited to surface protection, but penetrates into the stone for deep protection; It can not only protect the natural texture of stone, but also protect the permeability of stone. This is very important for stone protection. Therefore, the osmotic protective agent has excellent performance and broad development space. See table 1. 2 stone protectant research should grasp the direction and countermeasures
The research of stone protective agent in China should start with the structure of stone. Study on the composition and the nature of pollution sources; Synthetic permeable water-based protective agent is beneficial to stone protection. 2. 1 Most of the composition, structural characteristics and properties of stone have micropores, as shown in figure 1. Therefore, stone has water absorption (generally, the water absorption of granite is 0.1%~ 0.2%); Stone contains minerals and iron oxide. After absorbing water, the stone will have pollution problems such as rust spots, yellow spots and water stains. 2.2 The main manifestations and causes of stone pollution diseases are shown in Figure 2: The diseases of stone are mainly natural factors, human factors, minerals and iron oxide in stone, which enter stone through capillary holes, causing stone diseases, resulting in water stains, white flowers, fungus moss, yellow (rust) and other phenomena. Generally speaking, the causes of stone lesions and various pollution factors are mainly caused by the interaction with water. Without water, there is no frozen cracked stone; Without water, rust can't penetrate; Without water, fungus moss can't grow; Without water, salt can't penetrate into the stone and appear on the veneer, resulting in white flowers; Without water, carbon dioxide and sulfur dioxide, the stone surface cannot be dissolved, which makes the stone lose its luster. Therefore, the formulas for treating diseases are waterproof. 2.3 The main principle of research countermeasures and direction protection of stone protectant is: according to the principle of surface interface, the effective substance in the protectant permeates into the stone with the solvent, and after the solvent naturally volatilizes, the effective substance combines with the stone crystal to form a tough and transparent protective film, which prevents the penetration of external pollution and pollution from infiltrating into the stone interior and bottom. Overcome the shortcomings of wax protection, protect the stone from the inside, and protect the normal "breathing" of the stone-that is, good air permeability. The research of permeable water-based protective agent will be the research direction in this field in the future. Permeable water-based protective agent products should have the following excellent properties: 1, and dry hanging effect can be achieved by wet sticking construction; 2. No residual liquid is left on the surface to protect the permeability and natural texture of the stone; 3. Infiltrate the stone to form a water-blocking layer, enhance the light resistance and water resistance of the internal structure, improve the weather resistance and fatigue resistance, and achieve the performance of foreign products. The stone protected by this stone protectant should have the following seven characteristics: ① waterproof; ② Anti-fouling; ③ Anti-ultraviolet (delaying the fading time of stone); ④ Frost resistance and solubility resistance; ⑤ Keep the stone gas permeability; ⑥ Reduce the daily maintenance cost; ⑦ Repeated maintenance and convenient construction. To sum up, the problem of stone protection is imminent, and the research and development of permeability protection agent is imperative. This is a sunrise industry with broad market prospects. I hope more people will participate in the development of stone conservation in China.
For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd