The electrophoretic coating industry in the development and application of domestic
The electrophoretic coating industry in the development and successful application of the domestic -
One, overview
Study on coating technology of electrophoresis in more than 100 years ago, based on people on the metal surface anti-corrosion antirust requirements continue to increase and the related surface treatment technology can not solve this demand, and was gradually developed. Until 60 years before by George Dr. Brewer and Ford Motor Company successfully developed anodic electrophoretic paint. Coating line of the first used in the Ford Motor Company, with the production of anode electrophoresis paint, exposed the film contains a metal ion defects, poor corrosion resistance and therefore, cathode electrophoresis paint high corrosion resistance in the seventy's has been successfully developed, and has been approved and popularized application. After that, the electrophoresis technology development change rapidly, product variety by epoxy resin type to acrylic and polyurethane type. The protection of varieties of products from the auto industry extended to the bicycle, motorcycle and household appliances, light industry and jewelry industry, such as: air conditioning, TV, washing machine, motorcycle, glasses, locks, lighting and accessories, hair clips, tie clip and various metal industry as well as the aluminum surface antirust industry.
Advantage two, electrophoresis coating.
1, in a concave part, can form complete uniform protective film, and can be used to adjust the operating voltage is different, can control the thickness of the coating, achieve anticorrosive high, and eliminates the electroplating process of uneven thickness of electrode effect, but also eliminate the fault crust, tears in the painting process.
2, paint utilization rate is as high as 95%, compared with the painting method, reduce the waste of materials.
3, with water as solvent, avoids the risk of fire, also greatly reduces water and air pollution, improve security, reduce the cost of environmental protection equipment.
4, can reduce the noble metal coating thickness, still can maintain and beyond the original coating life, to replace the gold color electrophoretic paint, greatly reduced the cost of production.
5, high productivity, shortening the production time. Metal surface treatment, electroplating, coating and so on, after the completion of carrying large amounts of water, the traditional spraying method to be drying reproduction, time consuming and a waste of energy, and electrophoresis continuous operation, easy and automatic production.
Principle three, electrophoresis paint
Electrophoresis is the Yin and Yang of electrophoretic coating, applied voltage, with coating ion charges move to the cathode, and interaction with alkaline produced cathode surface formation of insoluble matter, deposited on the surface of a workpiece. It consists of four processes:
1, electrolytic (decomposition)
In the cathode reaction initially for the electrolytic reaction, hydrogen and hydroxide ions OH, this reaction caused by the cathode surface to form a high alkaline boundary layer, the cation and hydroxyl function become insoluble material, coating deposition, equation is: H2O → OH+H
2, the electrophoretic (mobility, migration)
Cation exchange resin and H+ in the electric field, moving towards the cathode, and the anion moves toward the anode process.
3, the electrodeposition (precipitation)
In the painted surface of workpiece, cation resin and alkaline cathode surface, neutralization and precipitation not sediment, deposition of workpiece to be coated.
4, the electroosmotic (dehydration)
The film coating of solid and surface of the workpiece is translucent, with most of the pores, the water is leaking from the cathode film row, under the action of the electric field caused by dehydration, coating, and coating adsorption on the surface of a workpiece, and complete the whole process of electrophoresis.
Four, different types of electrophoresis paint process and reason
(a) the electrophoretic paint epoxy electrophoretic paint is mainly used for large-scale industrial enterprises, on the corrosion resistance requirements higher, varieties are black, gray, red, yellow and other colors, mainly for the automotive industry, bicycle industry, motorcycle industry, household electrical appliance industry, electrophoresis paint is not transparent color.
1, process route
Hanging on to the cleaning, degreasing, water washing, water washing, pickling, water washing, surface conditioning, phosphorization, washing, water washing, water washing, water washing, electrophoresis, recovery, recycling, water washing, water washing, into the oven, hanging
2, the role of each station
(1) pre cleaning: removal of metal fragments and welding slag, the elimination of phosphating and electrophoresis potential dust source.
(2) skim: effective cleaning dispersing and get rid of the workpiece surface mineral oil, lubricant and stamping compounds, improve the phosphating effect and reduce into the electrophoresis film and electrophoretic coating drying flange and welding seam is easy to cause shrinkage of pollutants.
(3) hot water washing: effective treatment legacy base membrane surface.
(4): derusting pickling and activation of metal surface.
(5) surface: adjust the surface, to form a uniform density of phosphating film.
(6) washing and water washing: fully washed with water, to avoid the previous process of acid, alkali and salt into the electrophoresis tank pollution paint groove, influence of film. Pure water conductivity less than 5 μ s
(7) electrophoresis: the measurement of voltage and time, the formation of the electrophoretic film.
(8) the water recovery: recovery of water, reduce waste liquid paint, recovery and reduce the production cost.
(9): the film cured in the baking temperature 160 ℃ ~ 180 ℃, curing.
(two) acrylic and polyurethane electrophoretic paint
1, process route
Hung, organic solvent dewaxing, ultrasonic wax, hot water washing, cathode degreasing, degreasing, pickling, the impact of anode nickel (stainless steel) / pre copper (zinc pressure parts), acid copper, bright nickel, silver flash
This process is mainly for decorative requirements of workpiece, beautiful appearance and less corrosion resistance of light industry products, such as: glasses, lighter, locks, lamps, stationery, sports equipment and accessories hairpin industry, the electrophoresis coating to a transparent color, mix with a variety of color, in various plating process can achieve the effect of be riotous with colour bright, this process has been in the country
One, overview
Study on coating technology of electrophoresis in more than 100 years ago, based on people on the metal surface anti-corrosion antirust requirements continue to increase and the related surface treatment technology can not solve this demand, and was gradually developed. Until 60 years before by George Dr. Brewer and Ford Motor Company successfully developed anodic electrophoretic paint. Coating line of the first used in the Ford Motor Company, with the production of anode electrophoresis paint, exposed the film contains a metal ion defects, poor corrosion resistance and therefore, cathode electrophoresis paint high corrosion resistance in the seventy's has been successfully developed, and has been approved and popularized application. After that, the electrophoresis technology development change rapidly, product variety by epoxy resin type to acrylic and polyurethane type. The protection of varieties of products from the auto industry extended to the bicycle, motorcycle and household appliances, light industry and jewelry industry, such as: air conditioning, TV, washing machine, motorcycle, glasses, locks, lighting and accessories, hair clips, tie clip and various metal industry as well as the aluminum surface antirust industry.
Advantage two, electrophoresis coating.
1, in a concave part, can form complete uniform protective film, and can be used to adjust the operating voltage is different, can control the thickness of the coating, achieve anticorrosive high, and eliminates the electroplating process of uneven thickness of electrode effect, but also eliminate the fault crust, tears in the painting process.
2, paint utilization rate is as high as 95%, compared with the painting method, reduce the waste of materials.
3, with water as solvent, avoids the risk of fire, also greatly reduces water and air pollution, improve security, reduce the cost of environmental protection equipment.
4, can reduce the noble metal coating thickness, still can maintain and beyond the original coating life, to replace the gold color electrophoretic paint, greatly reduced the cost of production.
5, high productivity, shortening the production time. Metal surface treatment, electroplating, coating and so on, after the completion of carrying large amounts of water, the traditional spraying method to be drying reproduction, time consuming and a waste of energy, and electrophoresis continuous operation, easy and automatic production.
Principle three, electrophoresis paint
Electrophoresis is the Yin and Yang of electrophoretic coating, applied voltage, with coating ion charges move to the cathode, and interaction with alkaline produced cathode surface formation of insoluble matter, deposited on the surface of a workpiece. It consists of four processes:
1, electrolytic (decomposition)
In the cathode reaction initially for the electrolytic reaction, hydrogen and hydroxide ions OH, this reaction caused by the cathode surface to form a high alkaline boundary layer, the cation and hydroxyl function become insoluble material, coating deposition, equation is: H2O → OH+H
2, the electrophoretic (mobility, migration)
Cation exchange resin and H+ in the electric field, moving towards the cathode, and the anion moves toward the anode process.
3, the electrodeposition (precipitation)
In the painted surface of workpiece, cation resin and alkaline cathode surface, neutralization and precipitation not sediment, deposition of workpiece to be coated.
4, the electroosmotic (dehydration)
The film coating of solid and surface of the workpiece is translucent, with most of the pores, the water is leaking from the cathode film row, under the action of the electric field caused by dehydration, coating, and coating adsorption on the surface of a workpiece, and complete the whole process of electrophoresis.
Four, different types of electrophoresis paint process and reason
(a) the electrophoretic paint epoxy electrophoretic paint is mainly used for large-scale industrial enterprises, on the corrosion resistance requirements higher, varieties are black, gray, red, yellow and other colors, mainly for the automotive industry, bicycle industry, motorcycle industry, household electrical appliance industry, electrophoresis paint is not transparent color.
1, process route
Hanging on to the cleaning, degreasing, water washing, water washing, pickling, water washing, surface conditioning, phosphorization, washing, water washing, water washing, water washing, electrophoresis, recovery, recycling, water washing, water washing, into the oven, hanging
2, the role of each station
(1) pre cleaning: removal of metal fragments and welding slag, the elimination of phosphating and electrophoresis potential dust source.
(2) skim: effective cleaning dispersing and get rid of the workpiece surface mineral oil, lubricant and stamping compounds, improve the phosphating effect and reduce into the electrophoresis film and electrophoretic coating drying flange and welding seam is easy to cause shrinkage of pollutants.
(3) hot water washing: effective treatment legacy base membrane surface.
(4): derusting pickling and activation of metal surface.
(5) surface: adjust the surface, to form a uniform density of phosphating film.
(6) washing and water washing: fully washed with water, to avoid the previous process of acid, alkali and salt into the electrophoresis tank pollution paint groove, influence of film. Pure water conductivity less than 5 μ s
(7) electrophoresis: the measurement of voltage and time, the formation of the electrophoretic film.
(8) the water recovery: recovery of water, reduce waste liquid paint, recovery and reduce the production cost.
(9): the film cured in the baking temperature 160 ℃ ~ 180 ℃, curing.
(two) acrylic and polyurethane electrophoretic paint
1, process route
Hung, organic solvent dewaxing, ultrasonic wax, hot water washing, cathode degreasing, degreasing, pickling, the impact of anode nickel (stainless steel) / pre copper (zinc pressure parts), acid copper, bright nickel, silver flash
This process is mainly for decorative requirements of workpiece, beautiful appearance and less corrosion resistance of light industry products, such as: glasses, lighter, locks, lamps, stationery, sports equipment and accessories hairpin industry, the electrophoresis coating to a transparent color, mix with a variety of color, in various plating process can achieve the effect of be riotous with colour bright, this process has been in the country
