A new low VOC single-unit water-based polyurethane emulsion with excellent weather resistance has been successfully developed

China Paint Online News Information
First, policy background In recent years, the world has stepped up the prevention and control of environmental pollution problems, environmental protection regulations are becoming increasingly stringent. Therefore, the study of environmentally friendly coatings is particularly important. With the ministry of finance, the National Development and Reform Commission, the Ministry of Environmental Protection (fiscal and taxation No. 71) "Volatile organic sewage charges pilot measures" issued, the provinces have informed the pilot to levy VOC sewage charges, vigorously deploy air pollution prevention and finger-reinforcement measures, phase out organic solvent-based paint production and the use of organic solvent-based paint furniture manufacturing, wood products processing technology, and so on, to comprehensively promote the automotive manufacturing industry primer, medium paint, color paint and other innovative materials.January 26, 2015, the State Administration of Taxation and the Ministry of Finance issued the Notice on the Collection of Consumption Tax on Battery Coatings. With the approval of the State Council, a consumption tax on coatings will be levied from February 1, 2015. The paint is included in the scope of consumption tax collection, in the production, commissioned processing and import links, the applicable tax rate is 4%. No consumption tax is waived on coatings with volatile organic matter content below 420 g/L (inclusive) during construction., water-based paint promotion difficulties Due to the many disadvantages of organic solvent-based coatings, it is imperative to accelerate the promotion and application of water-based industrial paint. Water-based industrial coatings fundamentally eliminate or reduce environmental pollution caused by VOC emissions, saving resources. However, there are some constraints in the application of water-based coatings.First of all, water-based paint resin generally contains emulsifiers or hydro-based groups, paint also need to add hydro-friendly moist dispersants, thickeners and other additives, so water resistance is worse than solvent-based coatings, paint film corrosion performance is poor; Secondly, the moisture content of water-based paint is high, the energy required for water evaporation is higher than that of ordinary solvents, which affects the drying effect of spraying. Third, moisture in the wet paint film and steel for a long time contact, in the baking process is prone to flash embroidery; Finally, the water-like industrial paint has higher requirements for the temperature, relative humidity, ventilation control and baking temperature range during construction. Therefore, for the application-side enterprises, it is necessary to transform the coating line, greatly increasing energy consumption, the enthusiasm of the application-side enterprises is difficult to improve., the promotion and application of water-powered industrial paint is greatly restricted.III, the new VOC single-group water-based polyurethane emulsion research and development success For the above difficulties, Zhejiang Panj New Materials Co., Ltd. developed a new low-VOC single-group water-based polyurethane series emulsion. After testing, the series of emulsion comprehensive technical indicators to meet the established requirements, VOC content in line with the requirements of exemption from consumption tax, can be widely used in automotive paint / paint, advanced industrial painting, furniture building materials coating, container spraying and other fields. The emulsion has the following characteristics: 1. The emulsion is a single-part self-emulsified emulsion, without emulsion, not easy to foam, the resulting coating water resistance is good;。 2. Curing agent and the corresponding resin after a certain degree of thing reaction, the two are compatible, product quality is stable, uniform;。 3. The emulsion is water as a dispersion medium, can be diluted with water, construction utensils can be washed with water, construction is very convenient. Through the addition of water (the amount of added between 0-100%, pigments, etc., free adjustment of viscosity and solid content, suitable for different construction methods, low cost;。 4. Construction elasticity is large, adapt to a variety of climatic conditions, a variety of coating processes, baking temperature range of 120 degrees C-160 degrees C, can be directly sprayed on a variety of substrates (electrophoretic primers, plastic paint, stainless steel plates, hot-rolled coils, glass), wet film does not need to pre-bake, greatly save time and energy consumption, can be directly applied in the existing oily paint production, compounding and spraying system, without the need for new equipment, personnel and other inputs;。 5. The emulsion has good moisture dispersion for all kinds of pigments, can be used with organic/inorganic pigments, metal pigments, pearlescing pigments, to meet customer requirements for different colors of coating;。 6. Emulsion particle size is small, paint film finished with high gloss, good transparency, good adhesion, high hardness (3H), table dry speed, do not flow, no shrink holes and other defects, can be a perfect replacement for oily paint.。 7. Suitable for 3C2B process (three coatings and two bakes: primer pre-drying, color paint, varnish two coatings with wet touch wet finish coating), compared with the traditional 3C3B (three coating three baking) process, in order to meet all performance indicators, the premise can significantly reduce the cost of coating.
。