Transformation of solvent-based coatings - hydration of coatings

With the continuous improvement of energy stress and environmental protection laws around the world, VOC (volatile organic compounds) emissions are limited, the coating industry will move towards "four", that is, "water-based, photo-curing, powdering and high solid differentiation", low-solid solvent-based coatings will gradually be replaced.years, people pay more and more attention to water-based coatings, water-based coatings in the field of coatings is also expanding, has replaced a lot of solvent-based coatings. Water-based coatings in metal rust-proof coatings, home wood coatings, architectural coatings market share is high
china
. With the improvement of water-based coating performance, the market size of water-based coatings has been expanding since 2015. In 2017, the water-based coatings market was nearly 60 billion yuan, up 12% year-on-year. Water-based coatings are developing rapidly in automobiles, steel structures, furniture, containers, locomotives and other fields. Research and development of water-based resins at home and abroad is also being strengthened, among which soap-free emulsion polymerization, room temperature crosslinking technology, water-based photo-curing, water-based polyurethane correction is currently the focus of research in this field.film in water-based coatings is water-based resin, which is the most critical component of water-based coatings and determines the performance of water-based coatings. Water-based resin refers to a polymer system with water as its medium. It can be divided into water-soluble resin, water dispersion type and water milk type resin.
-soluble resin is formed by the polymer molecular chain with hydro-hydro-based group dissolved in water, is a molecular dispersion of the true solution, so the water-based resin is transparent state.
water dispersion resin is insoluble or not completely dissolved in water, through certain preparation and processing methods, so that it is dispersed in water, forming a water-based water dispersion liquid.
of water-dispersed resin and water-milk resin is relatively vague, many times there is no strict distinction, usually according to the size of the polymer dispersed particles in water to determine. The particle size of the water-dispersed resin ranges from
0.001 to 0.1 m
, while the particle size of the resin emulsion is
≥0.1 m
. The water dispersion resin is translucent and the emulsion is milky white.
With the development of water-based technology, there are many types of water-based resins, commonly used water-based aliclicic acid resins, water-based acrylic resins, water-based polyurethanes, water-based amino resins, water-based epoxy resins, water-based photo-curing resins and so on.water-based resins, because of water as a carrier, in the production or use of volatile substances significantly reduced the use, with many
advantages
:
production and processing process without fire risk;
Water has a wide range of sources and saves a lot of resources
toxic gases without organic solvents do not harm the health of front-line workers,
production lines and construction tools can be cleaned with water,
water-based coatings can be applied with electric deposition, high automatic production efficiency,
reduces VOC emissions and is environmentally friendly.
water-based resins also have some
soolability or bottlenecks
that limit their use in some applications:
water as a solvent, the need to increase the paint film drying and normal temperature drying time;
Water-sensitive materials such as paper, wood and other industrial products, water-based paint application is limited
,
use of organic amine neutralizers also have a certain toxicity, drainage wastewater if not treated will cause soil pollution

Runo Chemical, as a professional light-cured resin production enterprises, also pay close attention to the development of water-based resins, in 2017 began the research and development of water-based resins, set up a special water-based resin synthesis team, after two years of accumulation and improvement, recently launched a series of water-based resin products. Our water-based products are mainly for the coating application of plastic substrates, in this field of water-based coating applications have been a lot of performance bottlenecks, mainly the following problems:
due to the high surface pressure of water, the wetting of substrates is very poor, especially some low surface pressure of plastic substrates, very easy to appear coating defects. And by adding solvents or surfactants to solve this problem and dissolved in causing foaming, needle eyes and other problems;
and solvent-based resins, water-based resin on pigments or aluminum powder wet dispersion is poor, resulting in paint film color display or silver powder arrangement effect in general

For these application difficulties, Runo Chemical has specially developed three water-based UV resins and a water-based hydroxypropyl acrylic resin, the following is a description of the main features of these products.
FSP5290 is a ten-function water-based polyurethane dispersion, the resin curing speed, paint film hardness is high, has excellent wear resistance and water resistance, PU, plastic, bamboo substrate has a good adhesion, suitable for use in plastic or PU cover paint.
solvent-based UV single coating on the surface of the notebook computer coating application is very mature, HP and other terminal manufacturers hope that in the future can be water-based UV single coating to replace solvent-based coatings. This is a very big challenge for both raw material resins and formulation design, and based on our experience in solvent-based UV monocolor resins, we have developed two water-based polyurethane dispersions, FSP8946 and FSP8994. FSP8946 is a six-functional resin, with good silver powder qualitative arrangement performance, can provide the system with excellent wear resistance and water resistance, good wetting of plastic substrates. FSP8994 is a two-role resin with excellent silver powder directional arrangement performance and pigment wetting, while re-coating. Through the combination of these two water-based resins, we can obtain excellent surface effect and good complex.
we have also developed a hydroxypropyl acrylic emulsion FSP5286 for plastic substrates. This resin has good wetting properties on the plastic substrate, has excellent silver powder directional arrangement performance, with curing agent, can obtain excellent wear resistance and boiling water resistance, can be used as 2K PU paint. FSP5286 inter-layer attachment performance is also very good, so it can also be used as a 2K PU primer resin, in the PU primer can be directly sprayed with water-based UV paint, such a water-based two-coat system can make the material more stable.
From the market trend, water-based coatings in the future will have greater room for development, Runo Chemical will invest more energy in water-based resin synthesis and application, and constantly improve product performance, for solvent-based coatings to contribute to the transformation of their own strength.