The difference between water-based paint and solvent-based paint

1. Differences in coating systems

①The resin is different. The resin of water-based paint is water-soluble and can be dispersed (dissolved) in water, while the resin of solvent-based paint is insoluble in water.

②Diluent (solvent) is different. Water-based paints can be diluted by adding deionized water in any proportion, while solvent-based paints can only be diluted with organic solvents (odorless kerosene, light white oil, etc.).

2. the coating construction requirements are different

① As far as the construction environment is concerned, the freezing point of water is 0 °C, so water-based coatings cannot be applied below 5 °C, but solvent-based coatings can be applied above -5 °C, but the drying speed will be slowed down and the interval between tracks will be elongated;

② In terms of construction viscosity, the viscosity reduction effect of water is poor, and water-based coatings are more troublesome when adding dilution and viscosity reducers. Solvent type is easier to adjust the viscosity, and the viscosity limit will also affect the choice of construction method;

③For drying and curing, water-based paint is more “squeamish”. When the humidity is high and the temperature is low, the curing is not good and the drying time is prolonged. However, if the temperature rises and heats up, the water-based paint also needs to ramp up and immediately enter the high temperature environment. After the surface of the water-based paint dries, the overflow of internal water vapor will cause pinholes and even large areas of blistering. This is because there is only water as a diluent in waterborne coatings and there is no volatilization gradient. For solvent-based coatings, wax emulsions for paints india the diluent is composed of organic solvents with different boiling points and has multiple volatilization gradients. After flashing (the drying period after the construction is completed to the drying period before entering the oven), similar phenomena will not occur when entering the high temperature area for baking.

3. The difference of coating decoration after film formation

1. Different gloss performance

①Solvent-based coatings can control the fineness of pigments and fillers according to the grinding conditions, and are not easy to coarsen during storage. Changes in film gloss can be achieved by adding resins to control the coating PVC (pigment-to-base ratio) and additives (such as matting agents). Gloss can be matte, matte, semi-matte, high gloss. The gloss of car paint can be as high as 90% or more;

②The gloss performance of water-based paint is not as wide as that of oil-based paint, and the performance of high gloss is poor. This is because the water in water-based paints acts as a diluent. The volatile nature of water makes it difficult for water-based paints to exhibit high gloss levels above 85%.

2. Different color expression

① Solvent-based coatings have a wide range of pigments and fillers, whether inorganic or organic, so they can be adjusted to various colors and have excellent color expression;

② The selection range of pigments and fillers for water-based paints is small, and most organic pigments cannot be used. Due to incomplete shades, it is difficult to produce rich colors like solvent-based paints.

3. Difference between storage and transportation

Water-based paints do not contain flammable organic solvents, so they are relatively safe to store and transport. If contaminated, it can also be rinsed and diluted with plenty of water. However, the storage and transportation of water-based coatings have temperature requirements, and the thermal insulation transportation and storage are required to be carried out at -5 °C, otherwise there will be disadvantages such as demulsification.

4. Difference in function

Solvent-based coatings are mostly organic products. Organic products will have a series of problems such as chain scission and carbonization at high temperature. At present, the maximum temperature resistance of organic products does not exceed 400 ℃.

Special high temperature resistant paint The water-based paint contains special inorganic resin, which can withstand temperatures of thousands of degrees, which is an impossible height for solvent-based paints.

5. Differences in safety and environmental protection

Solvent-based coatings have potential safety hazards of fire and explosion during production, transportation, storage and use, especially in confined space construction, which is easy to cause suffocation and explosion. At the same time, organic solvents will also cause certain harm to the human body. The most famous case is the carcinogenic case of toluene, and the use of toluene is no longer allowed. The VOC of solvent-based coatings is high, and conventional products are even as high as more than 400. Enterprises are under great pressure on environmental protection and safety when producing and using solvent-based coatings.

Water-based coatings are environmentally friendly and safe in production, transportation, storage and use, and have made great contributions to energy conservation, emission reduction, safety and environmental protection in the corresponding national policies.