Waterborne coatings have become the mainstream direction of the modern coatings industry with their environmental protection, high efficiency and safety. It not only meets the increasingly stringent environmental protection needs, but also provides innovative solutions for coating applications in multiple fields. In the future, with the continuous breakthrough of technology, waterborne coatings will show their potential in more fields.
1. What is waterborne coating?
Waterborne coatings are a type of coating system with water as the main solvent or dispersion medium.
Compared with traditional solvent-based coatings, it significantly reduces the use of organic solvents and reduces the emission of volatile organic compounds (VOC), so it is widely regarded as a representative of environmentally friendly coatings.
2. Composition of waterborne coatings
The basic composition of waterborne coatings includes:
Film-forming substances: such as acrylic resins, polyurethane dispersions, epoxy resins, etc., provide the basic properties of the coating.
Pigments and fillers: such as titanium dioxide and calcium carbonate, used to provide color, hiding power and enhance the performance of the coating.
Additives: including wetting agents, leveling agents, dispersants, preservatives, etc., to improve the performance of coatings and construction effects.
Water: as the main dispersion medium or diluent, different from the organic solventsin traditional coatings.
The rational selection and use of substrate wetting agents is crucial to improving the performance and application effect of waterborne coatings, and is a key link that cannot be ignored in coatings research and development and production.
1) Definition of substrate wetting agents
Substrate wetting agents are a type of additives specifically used to improve the wetting properties of coatings on substrate surfaces. They reduce the surface tension of the coating, allowing the coating to spread evenly on the substrate surface, thereby improving the adhesion and smoothness of the coating.
2) Role in waterborne coatings
Since waterborne coatings use water as a solvent, the surface tension of water is high (about 72 mN/m), making it difficult to wet many substrate surfaces well, especially low surface energy materials (such as plastics, metals, etc.). The main roles of substrate wetting agents in waterborne coatings include:
Reducing surface tension: quickly wetting the substrate surface to avoid shrinkage or spots.
Improving coating performance: quickly wetting the substrate surface to avoid shrinkage or spots in the coating.
Enhancing adhesion
Optimizing appearance: reducing surface defects such as orange peel, sagging or pinholes.
3) Common types of substrate wetting agents
Silane wetting agents: highly effective in reducing surface tension, suitable for difficult-to-wet substrates, but may affect the recoating performance of the coating.
Non-ionic wetting agents: highly stable, with little impact on the coating system, widely used in various substrates.
Fluorinated wetting agents: significant surface tension reduction effect, suitable for special high-demand applications, but with high cost.
What are the substrate wetting agents we can provide?
1) Acetylenic alcohol ether modified silicone wetting agent
E520, which can replace Tego 4000
E530, which can replace Tego 4100
2) Polyether modified silicone wetting agent
S8240, which can replace Tego 240
S8245, which can replace Tego 245
S8270, which can replace Tego 270
PTS-845, which can replace Tego 450
PTS-8346, which can replace BYK 346
PTS-8408, which can replace Momentive 408
PTS-8077, which can replace Momentive 77
3) Acetylenic alcohol ethers wetting agent
PT-420, which can replace Surfynol 420
PT-440, which can replace Surfynol 440
PT-465, which can replace Surfynol 465
PT-2502, which can replace Surfynol 2502
PT-640, which can replace Dynol 604
PT-670, which can replace Dynol 607
4) Low foam wetting agent
DP-16, which can replace Solvay 106. Surface Tension Static: 29 Dynamic: 34
E-33, which can replace Tego W111. Surface Tension Static: 32 Dynamic: 34
E-22S. Surface Tension Static: 28 Dynamic: 35
We will attend 2024 Chinacoat Expo 3-5th Dec. in Guangzhou, China. Let's meet there!
