What kind of paint should I use for decoration? In the building materials market, you may see and hear the introduction of various functional coatings, some are anti-bacterial, some are anti-cracking, some are resistant to scrubbing, some are resistant to formaldehyde, and some are even resistant to fog Haze, can release negative oxygen ions... all kinds of effects can't help but make your heart beat. Faced with a dazzling array of paint products and various promotional functions, how to choose?
Special effects attract attention
In some building materials supermarkets, many coatings claim to have certain special functions such as antibacterial, anti-mildew, anti-cracking, and anti-formaldehyde, and "anti-formaldehyde" has almost become one of the "must-have" functions of coatings-a brand is fully effective The wall paint claims the innovative silver ion antibacterial technology, which can resist formaldehyde, benzene, and antibacterial; another brand of five-in-one suit also has the effect of "anti-formaldehyde".
Consumer Mr. Zhang said that he values the environmental protection of coatings very much. “I certainly don’t approve of the absence of anti-formaldehyde function. But no one can tell how much formaldehyde can be decomposed.” Consumer Ms. Zhou said that she often sees advertisements. Many products also advertise that they do not contain harmful substances such as formaldehyde and VOC. "I feel that the wall paint actually contains a lot of harmful substances. For the sake of insurance, it is better to choose a clean smell function."
Sales staff at some paint specialty stores said that the anti-cracking function can cover up small cracks on the wall, and the odor-cleaning function is that the paint itself is tasteless and can be used immediately. In addition to the odorless paint itself, the paint can also absorb the peculiar smell generated by other parts of the room, that is, absorb formaldehyde. "Efficacy is there, but many functions cannot be tested." When asked whether some paints that are resistant to formaldehyde and release negative oxygen ions can be tested indoors after painting, the salesperson said that "this service is not yet available. If you are not assured, you can ask a professional testing agency to test." The anti-cracking and scrubbing-resistant functional coatings cannot be demonstrated on-site, and can only be "experienced slowly" after use.
In fact, some consumers have questions about the additional functions of paint. Consumer Mr. Wang said that because he was worried about the formaldehyde pollution caused by decoration, he valued the paint brand very much. He believed that "for a wide range of painting, if unenvironmental paint is used, the consequences will definitely be unimaginable". After several "investigations", he valued anti-formaldehyde and anti-bacterial coatings very much, but he was puzzled that the merchants could not provide testing. "Are there any products that promote the effects?" It is understood that many consumers advertise the anti-formaldehyde coatings. And other additional functions are "preferred to have."
According to industry insiders, the additional effects of some coatings are actually very limited, and they are not as magical as advertised——
The best trapping agent for formaldehyde is water. Currently, there is no product that can absorb formaldehyde immediately. Even if the walls are full of trapping agents, it can only capture the formaldehyde near the wall, and the formaldehyde emission duration of some building materials indoors is 10~ In 15 years, there are also certain problems whether the paint can continuously capture formaldehyde for a long time;
The scrubbing-resistant paint is also very easy to be damaged if it is scrubbed for many times. Although the current paint requires to be able to "breathe" and be breathable and impermeable after molecular structure changes, there are still pores in the paint. As long as there are pores, it will be water permeable. Repeated scrubbing It may damage the paint surface;
The paint that claims to be able to release negative oxygen ions, although it can indeed release a certain amount of negative oxygen ions after testing, but the effect will be quite different from the advertised product.
Special effects are limited
Are there any relevant standards to define the various functions of coatings on the market? Tang Ying, secretary-general of the National Coatings and Pigments Standardization Technical Committee, stated that the current industry standard for functional coatings in the coatings industry was implemented on January 1, 2008. The standard divides products into two levels according to their anti-bacterial performance: Products with antibacterial properties greater than 99% are products with strong antibacterial properties and belong to Class I; products with antibacterial properties greater than 90% and less than 99% are antibacterial products and belong to Class II. In addition, the industry standard of "Negative Ion Functional Coatings" was implemented on June 1, 2010, which regulates the corresponding functional coatings currently on the market.
Regarding the performance of some products that claim to be able to resist cracking and mildew, Tang Ying said that whether the wall cracks is mainly related to the basic treatment of the wall, and has little to do with the paint itself. The paint can only play some auxiliary functions. The coatings with anti-cracking function are mainly exterior wall coatings. There are few products that can achieve anti-cracking function of interior wall coatings. Anti-mold is the function of the coating itself, but this is under normal conditions, and if it breaks through a certain temperature and Humidity may also produce mildew.
In view of the additional functions claimed by some coatings on the market, relevant experts have made detailed analysis——
Basic function is the key
At present, many consumers regard "anti-formaldehyde", "clean taste", "antibacterial" and other functions as important factors in choosing coatings. However, little attention is paid to basic functions such as "waterproof", "anti-cracking", and "anti-mold".
"The decoration and protection of the home environment is the main function of the paint. The formaldehyde content of the interior wall paint itself is very low and basically undetectable. Compared with the furniture floor, the formaldehyde content is almost negligible. Consumers should not Auxiliary functions are used as a reference for purchase.” A person from the China Coatings Industry Association said that although an indoor floor of 100 square meters will bring about 300 to 350 square meters of wall coating area, in fact, the impact of paint on indoor environmental protection is relatively limited. It is not the focus of indoor air pollution. Some consumers pay too much attention to the environmental protection performance of coatings because "the focus has been misplaced." When buying coatings, you should pay more attention to its most basic functions-
According to reports, a good quality paint should have good lubricity and consistency, and smell a light fragrance. Pay attention to the production date when purchasing paint. Once the paint exceeds the shelf life, emulsion and liquid separation will occur, and a chemical reaction will occur under the action of temperature, which will reduce the adhesion and affect the quality. When buying paint, you can’t just pay attention to the top coat and ignore the primer. The function of the paint primer is different from that of the top coat. The primer contains the paint’s adhesion, anti-mildew, anti-corrosion and other special effects. If you only buy the top coat If you don't buy a primer, you may not achieve the desired effect after the paint is applied.
"The choice of paint should pay attention to the adhesion of the paint and the content of VOC, especially the VOC content is the most important criterion for judging the quality of the paint. The adhesion of inferior paint is very poor, and it is easy to cause peeling, cracking and even peeling." Tang Ying said that the current brand differentiation in the coatings industry is very obvious. Some big brand coatings have launched new functional coatings. Compared with some coating brands that lack branding, the formulation of the coatings is relatively stable, which can ensure environmental protection indicators and quality performance, but for some Special auxiliary functions, consumers should be cautious when buying.