Discussion focused on the development and future of automotive coatings

Paper Keywords: car paint green energy trends

Abstract: According to the current global automotive industry continues to change the characteristics of paint, car paint more and more people's attention. Describes the function of automotive coatings, fuel-efficient vehicles on the market of environmentally friendly coatings, and the newly developed energy-saving environmental protection car paint, car refinishing coatings; also pointed out that the development of environmentally friendly coatings is that people always pursue and future trends, high-tech coatings have come out for the new century, the development of automotive paint coatings to create a bright future.

The development comes at a new automotive coatings business

Global automotive coatings industry is currently $ 3.4 billion in total sales, the market continued to change the main characteristics of this industry, although competition is very fierce, but the cooperation between the various competitors and joint venture projects are extremely common, this is because all competitors have the same goal, that is, through product innovation to meet environmental and user requirements.

Automotive industry over 100 years of history, since the car since the birth, especially in the last 20 years, vehicle paint coating has been rapid development in the automotive industry in developed countries, the amount of car paint in the paint production occupies an extremely important position, generally after the building with paint, but paint the largest share of sales, higher than the architectural coatings, therefore, attach great importance to national paint manufacturer of automotive coatings trends and development to meet the car industrial development, automotive paint production and technology development are groups, international trend. With the growing emphasis on environmental protection, pollution began to apply paint High temperature solid component polyurethane paint, acrylic polymer ammonia, vinegar, paint and varnish are widely used because of the high gloss coating and the use of transparent, making the defect more easily exposed, so the material preparation and clean workshop environment is more important than ever, so we had a downdraft spray booth ventilation while pearl paint coating technology has been refined using the 2-layer 3-layer coating and painting, so that the color of the body more beautiful and have a sense of illusion .1982, Nissan's use of powder coating, the mid-1980s, GM Motors truck plant in the use of powder coating, powder coating has been started in the middle of the coating was thick with .1984 cathodic electrophoretic coating plant started in the automotive, coating thicker than 30 um. Later, many automobile plant and from the thick Go to the cathodic electrodeposition coating film thickness of cathodic electrophoretic coating, film thickness of 25 um or so, has the same thick-film cathode electrophoresis paint good corrosion resistance.

In recent years, with a color intermediate coating has been widely used in the United States, its main advantage is in the color and finish painted color matching, improved cosmetic appearance due to the use of colored coating, finish in metallic basecoats The thickness can be reduced from 20 um 15 um, and metallic paint can reduce the amount of cover to 25 um. This reduces the amount of paint to avoid sagging and other ills, reducing the return rate. China's car manufacturers used finish, in the late 1960s to the mid-1980s, are generally used in low-mass fraction of the amino-amino paint .1985 after high mass fraction of the amino-amino paint, with the car industry, acrylic resin enamel paint, enamel and high-quality amino resin layer paint coating process along with the introduction and application of a number of cars in the new .80 body painting line late in the part of the car to start using water-based metallic coating line at the end of the flash paint, water-based automotive coatings to the surface by the end of the gradual development, has water-based primer, starting in the water-based coating. into the 1990s, the use of water to speed up the pace, especially in Europe, coated in paint has been to achieve a water-based Japanese water-based research work has been completed, Nissan Motor Company began to use water-based paint in the coating, but because of high production costs, environmental requirements are not stringent in Europe and America, so do not promote the use of Japanese.

1990s, a group of acid rain, scratch-resistant paint cars, water-based coatings, high solids coatings and powder coatings and other environmentally friendly coatings have been developed and has been widely available for industrial applications. ICI has successfully developed the epoch-making water-based coatings, are the major automobile manufacturing companies are increasingly using this coating. Solid high abrasion-resistant paint and varnish composition has also been successfully developed, has begun to be Nissan, Toyota and other auto plants use the same time, the color the promotion of parent coating, isocyanate-free silicone coating covers the bottom layer of a transparent heat-safe polyurethane paint and a number of high-tech coatings have come out for the 21st century, the development of automotive paint to create a bright future.

2 car paint more and more cause for concern

Automotive finish protects the car from corrosion and beautifying effect, is the vehicle one of the most important indicators of quality because the spray paint cars accounted for 20% of the total cost of production, and the outer surface of the car is painted more than 90% surface, obviously the quality of the coating (gloss, color, durability, etc.) will directly affect the appearance, affect people's evaluation of the quality of the car, so car manufacturers attach great importance to car paint technology, often invest huge money and manpower to develop and improve the car's finish, emphasizing the first to seize the visual impression. topcoat of the paint and ordinary metallic paint, pearl paint mainly three kinds, and now many car paint with metallic and pearlescent paint, spray the then spray varnish finish, the whole body can be bright as a mirror and now the car body coating process is generally carried out in accordance with these procedures, the general car body to three-layer coating, the cathodic electrodeposition primer, and paint coating composition, Some high-class car body to spray 4-5 layer by cathodic electrodeposition primer, the coating layer and finish 1 - 2 1 1 2 layer in order to achieve a higher decorative appearance. Image rate car paint requirements high, bright as a mirror in addition to the quality of the paint, but also have very high requirements of the workshop environment and technology from the vehicle body painting to baking process, the workshop to the air clean, can not have excessive dust due to technology progress, today's spraying and spraying more than ten years ago, great progress has been compared, regardless of paint color, Bo nodal, additives, stabilizers, dissolution systems and technology have changed, and this change is still ongoing, so the quality of cars has been greatly improved finish in the modern factory, paint color, painting methods have been computerized management.

Into the new century, China's automobile industry has made considerable progress, more car ownership is increasing at an alarming rate, one of the most notable is the rapid increase in the number of cars, vehicle ownership is also increasing the proportion of large variety of shapes, colorful composition of modern city traffic has beautiful landscape. sedans can play a role in beautifying the city, in its unique shape and beautiful exterior, but no matter how good the quality of automotive coatings, in the course of , climate change, caused by exposure to a variety of reasons, rub cut, or even crash, and many other reasons will lead to paint deterioration, damage. how to maintain and restore the appearance of good cars, auto repair industry has drawn increasing attention.

3 newly developed energy-saving automotive coatings

In the past 10 years, automotive paint in its weather resistance, stone impact resistance, the appearance of decorative, ornamental and other high arts have made great progress, as people's awareness of environmental protection, the automotive paint and faced with new issues.'s recent demand for automotive coatings is to improve the coating quality, protecting the environment and reduce costs. In response to these demands, starting their own paints from paint factory, a lot of research, developed a series of greater value in use new paint.

3.1 electrophoretic coating

As a bottom line of the cathodic electrodeposition coating vehicle in 1977 at Ford Motor Company began to use, when cathodic electrodeposition coating thickness of about 20 um thick cathodic electrophoretic coating In 1984 manufacturers began to use in the automotive, coating thickness of more than 30 um or more later Many automobile manufacturers and from thick to medium thick cathodic electrophoretic coating cathodic electrophoretic coating, film thickness of about 25 um, with a thick cathodic electrophoretic coating with good corrosion resistance also. Currently, the world's automobile production, 92% use electrophoretic coating (ED), of which 90% of the cathodic electrophoretic paint (CED). Cathodic electrodeposition coating has excellent permeability, depression can even cover parts of the workpiece, and a strong anti-corrosion properties, resistance to salt spray of up to 1 200 h. leveling a new generation of high cathodic electrophoretic paint has been used in the U.S. auto manufacturers. The representative products are PPC, Edl l thick cathodic electrophoretic coating, Ed12 in thick cathodic electrophoretic coating, DuPont Cormax TM thick film or thick film cathode electrophoretic coating in its major performance improvements is to make the film surface roughness decreased For example Cormax TM in the thick cathodic electrophoretic paint film surface Ra 0. 15 to 0. 20 um
Automotive primer using CED foregone conclusion, but it was suggested that the use of powder coating as a primer and the coating, while the CED will not change direction. The main future work is to further improve performance, such as reducing the solid temperature, increase the smoothness and durability .

3.2 intermediate coating

Water-based automotive coatings to the surface by the end of the gradual development, has been water-based primer, .20 in water-based coating began the late 1980s, in some cars start using water-based coating line metallic basecoats, into the people in the 1990s, accelerated the paint water-based pace, especially in Europe, the painted coating has been achieved water-based Japanese water-based research work has been completed, Nissan Murayama plant using Japanese oil produced water the coating paint. in the middle of the coating powder coating has started to use .1982 in Japan Nissan uses powder coating, the mid-1980s, General Motors truck plant in I use a powder coated, in recent years in the three Small powder coating used on trucks, but powder coating production line in the input before, there are several major difficulties. The biggest difficulty is how to form a smooth uniform coating, the particles of powder particle coating device technology and the stability of supply today, and the development of coatings and coating methods have made progress, the original solvent-based coatings than the poor appearance of the coating is also improved, stable supply of paint and transfer efficiency improvement is possible. In recent years, with a color intermediate coating has been widely used in the United States, its main advantage is in the color and finish painted color matching, improved cosmetic appearance due to the use of colored coating, finish in metallic background paint thickness from 20 um down to 15 um and metallic paint can reduce the amount of cover to 25um. This reduces the amount of paint, reducing sagging and other ills, reducing the return rate.

3.3 finish

Two types of car paint, metallic paint, and that the paint, each roughly 1 / 2 series in recent years, the rapid development of metallic paint, pearl paint, coatings and other endless dream, to have a high color clarity, depth sense, high color direction. Links to free download http://eng.hi138.com
metallic paint in the United States most of the high-solids paint flash, and the Japanese use the most is the low-solid metallic paint With increasingly stringent environmental regulations, in order to improve the appearance of luxury cars of the film quality, the U.S. part of the past two years, using water-based limousine metallic paint, can greatly reduce the volatile organic compounds (VOC) emissions while water-based metallic paint has a special rheology conducive to aluminum directional, better than solvent-based coatings of metal effect, so the water-based metallic paint painted earlier than the water in the Japanese automobile plant acceptance, Europe has also been widely used. waterborne metallic paint is the inevitable trend, technology has matured, can quickly promote the use of General Motors expects 2020 world's most water-based car plant will use about .5 a metallic paint car factory in the country may be water-based metallic paint needs. waterborne metallic paint instead of solvent-based metallic paint, with all water-based paint, must have constant temperature and humidity conditions, the general construction of a temperature of 22 a 28 ℃, relative humidity of 60% to 80% water-based metallic paint After construction, there must be a flash-off process, usually 90 ℃, 5 min or so, so that evaporation of water before spraying two-component high-solids acrylic paint or powder coating.

Whether to cover the paint on the varnish, the general view that the cover varnish, the film looks, durability has been enhanced, so that all the U.S. car company Chrysler, General Motors paint on some cars in this re- cast a layer of varnish, the paint film to improve the appearance of present use in Europe and North America are two-component or single-component high solids acrylic varnish, but isocyanate vinegar an acrylic system defects isocyanate vinegar is toxic, therefore, from the environmental point of view, the future of varnish should be powder coatings and water-based paint present, varnish and the paint and high-solids coatings production line is now easily accepted in the application is still mainstream if we adopt the two-component high solids coatings, construction of up to 85% solids, VOC emissions and water-based paint has been similar to the recent feasible. powder coating is the most promising of the varnish, but as a character paint, the color change is difficult, subject to certain restrictions on use.

4 eco-friendly automotive coatings is that people always seek

As human society continues to advance and continuous improvement, automotive and related industries are bound to keep up with the pace of the times, all aspects of society continue to meet the new requirements proposed for coating, these requirements are for improve and enhance the paint itself, while others paint for use restrictions for environmental pollution.

Since the car was born, after decades of paint workers who work as a motor vehicle, one of the important supporting materials, the coating properties such as decorative, anti-corrosion, anti-stoning resistance, workability and durability and so With the large degree of enhancement and improvement, largely to meet the needs of the automotive industry, but the pursuit of perfect demand is endless, development and production of high-performance automotive coatings is always the subject. to protect the global environment, reducing air increasing demands for pollution, environmental problems are also very strongly about the automotive and related industries, therefore, high-solids differentiation, waterborne and powder technology, from the 20th century has been the world's paint industry to develop new products basic principles and direction of development.

Automotive coatings industry is facing one of the most important environmental issues such as long-term production for the car will emit large quantities of solvent-based coatings VOC, in order to solve this problem, the U.S. federal government asked the country's three major car manufacturers (General Motors Corporation (GM), Ford Motor Company and Daimler-Chrysler 'joint development and production of advanced environmentally friendly paint products. According to reports, although the powder coating environmentally friendly and low cost However, paint coating equipment such as high cost, leading to the construction cost is much higher than conventional paint solvent-based coatings, so even if the research is successful, this technology may still be some time before the full applications.

In order to reduce pollution emissions coatings, General Motors, Daimler-Chrysler and Ford Motor Company vehicles are used for powder coating paint on the performance of the relevant tests in order to promote the application using powder varnish other than the use of powder coatings more demanding, more difficult, because not only give a varnish coating provide gloss and bright, but also anti-fade protection Suila and the traditional form of mist spray varnish to the surface in the car, will be released during the drying process of VOC, pollution of the environment. In addition, the liquid paint overspray or to escape must be collected and landfill disposal, and this is not from a sound ecological measures. The fog particles form a dry powder coating without using any solvent, for spray outside the Plaza can be part of the collection, filtration and recycling, with the new powder coating line for the production of other hybrid cars, reducing the process to bring the car spraying the environmental impact.

In addition to powder varnish, the recent LEPC also announced it has launched two new research projects: water slurry powder varnish and paint Bo knot powder primer. PPG Industries that, from cleaning and pre-coated decorative coating to increase and varnish varnish, you can develop some environmentally friendly materials to improve the impact on the environment, for example you can change the chemical properties of materials and application methods, but can also improve transport efficiency, materials recycling rate and reduce or eliminate waste and other aspects to improve the environmental impact of various work order to meet environmental regulations, many companies are currently produced from their coatings, especially from the pre-removal and anti-corrosion products, chromium, nickel and lead heavy metals. In addition, there are other companies are also used for protective coating of other technologies to study. BASF also introduced Ureclear varnish, it is a kind of two-component nature of the amino acid B vinegar B vinegar, one-component urethane varnish by the use of this amino acid chemical properties of vinegar, BASF has no longer need to environmentalists in recent years has been subject to violent attacks isocyanate cool, the company said they will continue to focus on the economic and environmental aspects, and its research and development program called EC02 developed a comprehensive strategy such as the company is working with car manufacturers test the powder with the varnish water slurry (a mixture of liquid and powder coating the body). to produce the powder coating, it would be dispersed in water, and then use traditional liquid paint coating equipment spraying, powder coating disadvantage of this is difficult to control film thickness, etc. If made of liquid paint, you can better control the film thickness, and this mixture contains zero VOC.

Cost, quality and environmental issues will continue to affect the automotive coatings market, paint suppliers and car manufacturers are looking for a shorter best way to paint the circulatory system, which will bring enormous business opportunities automotive industry, while manufacturers also study a coating layer with a layer 2 or even instead of the new multi-layer coating technology to reduce drying time for consumers, no matter what technology manufacturers to adopt or use any paint, as long as the performance is good enough to meet requirements, but the responsibility for the whole community, it must be based on a reasonable cost to produce good quality, customer satisfaction, environmentally friendly products.

5 Conclusion

In the automotive industry in developed countries, the amount of car paint in the paint production occupies an extremely important position, generally after the paint used in construction, but it paints the largest share of sales, and higher than the architectural coatings. Therefore, countries attach great importance to automotive paint manufacturers paint developments and development to meet the development needs of the automotive industry, automotive coatings manufacturing and technology development with the group, international tendencies in the past l0 years, in its automotive coatings weather resistance, stone impact resistance, the appearance of decorative, ornamental and other high arts have made great progress, but as people's awareness of environmental protection, making the car paint and faced with new issues. today for automotive coatings requirement is to improve the coating quality, protect the global environment and reduce costs. In response to these requirements, paint manufacturers starting from the paint itself, a lot of research, developed a series of new paint.

With the growing national emphasis on environmental protection, in the 21st century automotive paint the major trends, in addition to the need to adapt to market competition and catch up with new trends, efforts to improve the car's exterior decorative coating (high gloss, high distinctness of image of, multi-color, increase three-dimensional, etc.), anti-rub resistance, and resistance to stone hit the polluting environment on film, it must also reduce automobile coating process on the environment. for the new century automobile paint coatings development to create a bright future. Links to free download http://eng.hi138.com

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