Current situation and development trend of the hot

2022-09-22
  • Detail

Current situation and development trend of steel drum packaging coatings (2)

Second, the development of powder coatings is rapid

in the coating industry, powder coatings belong to the fastest-growing category. Due to the serious air pollution in the world, environmental protection regulations are increasingly strict on pollution control, requiring the development of pollution-free and resource-saving paint varieties. Therefore, powder coatings, which are solvent-free, 100% converted into films, and have comprehensive protective and decorative properties, have achieved rapid development because of their unique economic and social benefits

the main varieties of powder coatings are epoxy resin, polyester, acrylic acid and polyurethane powder coatings. In recent years, aromatic polyurethane and aliphatic polyurethane powders have attracted attention for their excellent properties

III. Development Trend of high solid coatings

with the increasing strengthening of environmental protection measures, high solid coatings have developed rapidly. Among them, amino, acrylic and amino acrylic coatings are widely used. In recent years, moBay company of the United States has developed a new type of finish paint for the coating assembly line for metal packaging. This high solid, one component polyurethane modified polymer system can be used on rigid and flexible substrates, and has excellent acid resistance, hardness and pigment kneading. Using aliphatic polyisocyanates such as dsemodurn and polycaprolactone, polyurethane coatings with solids up to 100% can be made. The coating has good properties and ordinary construction methods. The two-component thermosetting polyurethane coating prepared with dsemodurn and various hydroxyl acrylic resins has a solid content of more than 70%, low viscosity, easy to apply, and can be cured at room temperature or low temperature. It is a very ideal decorative high solid polyurethane coating

IV. progress of UV curable coatings

UV curable coatings are also solvent-free and energy-saving coatings. Originally, they were mainly used for wood and furniture. At present, they are widely used in the coating field of wood and plastic packaging products. In Europe and developed countries, the UV curing type has great market potential and is favored by large enterprises, mainly due to the needs of flow operations. There are more than 700 large UV curing coating lines in the United States, and about 40% of wood or plastic packaging materials in Germany and Japan use UV curing coatings. Recently, polyurethane acrylic acid light curing coating has been developed, which is made by dissolving polyurethane oligomer with acrylate end group in active diluent (photopolymerizable acrylic monomer). It not only maintains the characteristics of acrylic resin UV curing coating, but also has particularly good flexibility, adhesion, chemical corrosion resistance and wear resistance

v. the trend and development of several special coatings

1. Antifouling coatings

in recent years, sigma company in the Netherlands has successfully developed a new type of antifouling coating without Tin. Its self polishing property is the same as that of the existing antifouling coatings with tin, but its anti shrinkage and anti cracking properties are much better than other antifouling coatings without Tin. Recently, Kansai coating company in Japan developed a non-toxic antifouling coating called captain crystal, which does not contain organic tin and cuprous oxide. As a coating to improve the earth's environment, it can effectively prevent the pollution of packaging materials, and the duration can reach 5 years. The Japanese oil company has successfully developed a new type of anti pollution and acid rain resistant PCM coating by using super crosslinking technology. Experiments have proved that this technology can make automotive coatings have excellent pollution resistance, its weather resistance is eight times that of acrylic resin series coatings, and its film hardness can reach 3 ~ 4H

2. Anticorrosive coatings

foreign countries attach great importance to the development of long-term anticorrosive coatings. The main varieties include inorganic zinc rich paint, epoxy asphalt, vinyl resin, thick paste chlorinated rubber, solventless epoxy polyamide, solventless epoxy mortar and spguard coating. A long-term anti-corrosion coating composed of bisphenol A epoxy resin, isophthalic acid unsaturated polyester, epoxy acrylic resin and other base materials filled with 20% - 30% flake glass powder is used for the coating of marine facilities, and its anti-corrosion life is more than 10 years. In recent years, the development of anticorrosive coatings in China is relatively fast. For example, the epoxy coal tar pitch anticorrosive coating has been successfully developed by Shaanxi Yuanyuan Chemical Co., Ltd. the coating has strong adhesion and can be directly painted on the steel with rust layer, with good anticorrosive effect. The oil field anti-corrosion coating was successfully developed by Zhengzhou Institute of technology and Zhongyuan Oilfield Exploration and Design Institute. The coating has excellent corrosion resistance and good low-temperature moisture curing characteristics. Organic titanium coating, as a high-tech anti-corrosion coating in the plastic machinery industry, will increase by more than 12% every year on average. The Research Institute of Jilin chemical industry company has successfully studied this kind of non-toxic organic titanium coating, whose corrosion resistance has reached the level of similar foreign products, and can be used for anti-corrosion equipment in chemical, marine and other fields

3. Cathodic electrophoretic coating

this kind of coating has developed rapidly abroad and made many new achievements. Among them, the most representative ones are the development of thick film cathodic electrophoretic coatings, low temperature curing cathodic electrophoretic coatings and color cathodic electrophoretic coatings. Thick film cathodic electrophoretic coating is a new type of cathodic electrophoretic coating developed by PPG company in the United States, with excellent properties; Low temperature curing anionic electrophoretic coating is a new variety jointly developed by Japan Shendong coating company and Japan oil company in the late 1980s. The standard curing conditions of the coating are: 130 ℃/20min or 160 ℃/5min; Color cathodic electrophoretic coating is developed by Kansai coating company in Japan. It is based on epoxy resin, cross-linked with special isocyanate, and combined with the third component acrylic resin, which can be uniformly deposited in electrophoresis to form a composite film. This technology can make epoxy resin cathodic electrophoretic coating colorful and improve the weatherability of the coating. The development direction of cathodic electrophoretic coating is: thick film cathodic electrophoretic coating, which will solve the paint film deposited during electrophoretic coating and (2) strive to improve the viscoelasticity control of paint film in the baking process of a batch of advanced basic materials, so that the film formed at one time is relatively thick and the appearance is flat; Low temperature curing cathodic electrophoretic coating, develop low temperature curing coating with baking temperature of 130 ~ 140 ℃, and keep corrosion resistance and other properties unchanged, so as to be used in plastic, metal and other packaging, save energy and reduce cantilever material pollution; The edge antirust cathodic electrophoretic coating requires to reduce the fluidity of the film during dissolution and improve the edge coverage of the film, so as to improve the corrosion resistance of the edges of the cathodic electrophoretic coating. China should focus on developing thick film cathodic electrophoretic paint with a film thickness of 30-40 microns and a salt spray resistance of 1000 hours and ordinary cathodic electrophoretic paint with a salt spray resistance of more than 720 hours

VI. development trend of other relevant aspects

in order to meet the needs of improving the performance and variety of coating products, we should also constantly improve the performance of the required pigments. Organic pigments, such as azo series, phthalocyanine series and anthraquinone series pigments with excellent sun resistance and solvent resistance, will be widely used

expanding the use of auxiliary materials in coatings is becoming more and more important for the development of coatings. For example, the application of UV absorbers in coatings can improve light resistance; Antioxidants can improve aging resistance; With the development of waterborne coatings, the variety of wetting agents will continue to expand; UV curing agent is needed in the coating dried by UV. These auxiliary materials will be more widely used in the future

the application of computer in the coating industry can improve the coating formula, optimize the design of large-scale industrial production and production facilities, and quickly solve the problems of coating research, production, application and sales, resulting in low self-sufficiency rate; 2. Technical and management problems arising from the long-term failure of core technology. With the increase of coating demand and product varieties, the coating production process also needs to be continuously improved. The general trend of improvement is to further simplify the process, improve productivity, and realize continuous and automatic production. In the future, jet technology, silicon controlled technology and nanotechnology will be widely used in the coating industry, so that the degree of automation of production will reach a new level

Copyright © 2011 JIN SHI