Common knowledge of coating: steps of construction technology of water-based paint for plastic parts

Core tips: 1.1 storage and transportation of waterborne paint Water based paint has some special requirements for storage and handling Because of the nature of water, the water-based paint is very sensitive to temperature If the water-based paint is stored in the environment below zero degree, the solubility of the paint will change, resulting in the precipitation of some important components in the paint In this case, the waterborne paint will become uneven and may precipitate grains Even if such water-based paint is reheated, it will not be able to return to a uniform state, and the characteristics of the paint will be completely destroyed On the other hand, due to the water contained in the paint, the water will be stored in traditional way Shenyang steel structure fireproof coating construction expert punde Building Fire Engineering Co., Ltd Recommended introduction: since its establishment, Shenyang punde Construction Fire Engineering Co., Ltd has cultivated a group of professional construction teams with excellent equipment, rich experience and serious responsibility with advanced and scientific management methods and strict engineering quality assurance and after-sales service system It has undertaken a number of fire system installation projects, which has been praised by customers Every idea and special requirement of you will be fully considered by us and fully realized in the construction technology, which will become the cornerstone of our successful long-term development We are looking forward to your invitation, to provide you with quality services and high-quality technical support! All construction coatings have passed ISO9001 Paint Home News: 1.1 the storage and transportation of waterborne paint has some special requirements for storage and handling Because of the nature of water, the water-based paint is very sensitive to temperature If the water-based paint is stored in the environment below zero degree, the solubility of the paint will change, resulting in the precipitation of some important components in the paint In this case, the waterborne paint will become uneven and may precipitate grains Even if such water-based paint is reheated, it will not be able to return to a uniform state, and the characteristics of the paint will be completely destroyed On the other hand, because the paint contains water, the water will corrode the traditional container for storing paint, and the paint itself is easy to be affected by the divalent iron ion and change its rheological properties This requires that all containers for storing water-based paint must be made of stainless steel or plastic The temperature condition is 5-30 ℃ In the process of transportation, it needs to be heated or cooled according to the ambient temperature The vehicles for transportation must be able to control the temperature The water-based paint storage area and paint mixing room must have the temperature control function Generally speaking, the water-based paint can be stored stably for 3 months, and the paint needs to be reevaluated beyond this time, otherwise the spraying quality cannot be guaranteed The specific storage time may vary slightly depending on the paint supplier For the paint mixing room, the ambient temperature should be controlled at 20-28 ℃ If necessary, a heat exchanger can be used to maintain the paint temperature So the best way of storage and transportation is to keep the water-based paint at a relatively constant temperature, so that when adding new paint, there is no need to adjust the temperature 1.2 viscosity control is a very important process parameter for traditional paint For water-based paint, the concept of viscosity is quite different from traditional solvent based paint solvent The viscosity of the water-based paint is greatly affected by the shear force In the environment of low shear force, such as static placement in the container, it can reach a very high viscosity In the moment of circulation in the pipeline or spraying through the color change valve of the automatic spraying machine, due to the effect of high shear force, the viscosity of the water-based paint can be reduced a lot The viscosity of traditional solvent based paint changes little with shear stress Generally, we use Fisher or Ford cup to test the viscosity of solvent based paint For water-based paint, we can use a similar method The difference is that we use din cup with larger aperture, and the measured time does not represent the viscosity of the water-based paint, but its flow time In order to get the true viscosity of water-based paint, it is necessary to use special equipment, such as rotary viscosity tester, to measure the viscosity of water-based paint under different shear forces 1.3 construction characteristics of water-based paint in view of the high water content of water-based paint, all appliances in the spray room must be stainless steel or plastic, and cannot be mixed with other appliances of solvent paint system Temperature and humidity are the most important process parameters to be controlled in the spray room The recommended temperature is 25 ± 2 ℃ and humidity is 65 ± 5% Due to the good insulation of plastic parts, the surface resistance is usually more than 1012 Ω, It is easy to cause the accumulation of static charge In order to adapt to electrostatic spraying, coating conductive primer on plastic parts has become the mainstream of electrostatic spraying process of plastic parts in automobile industry The theoretical value of the general conductive resistance is less than 106 Ω, and in practical application, the most important additive in the production of waterborne paint is rheologic control agent or RCA, which can meet the production requirements by interacting with dispersed polymer particles The interaction has an important effect on the rheological properties, which makes the metal paint with low solid content obtain very high flop effect In addition, RCA can make the monochromatic paint obtain higher film thickness without sagging or color difference The repair process of spot repair is basically the same as that of solvent based paint, and the repair material can be directly applied to the online waterborne paint When baking at high temperature, it is necessary to control the heating rate, and too fast will lead to pinholes It is recommended to use hot air before baking with baking lamp Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire 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