Guangzhou Jinwei Chemical Co., Ltd

Automotive Refinish Paint One Stop Supplier. Professional Team, Perfect Service!

About Jinwei car paint/auto paint/automotive refinish applications and usage, Solid content and Viscosity
- Mar 13, 2018 -

image.png

While the term “high solids” is commonly used within different markets including adhesives, sealants, paints and coatings, there are no standards defining the minimum or average solids content of high solids formulations in general. 


“Solids” can refer to the non-volatile materials or the inorganic components of a mixture. Depending on the chemistry of the raw materials, high solids compositions take on a wide range of viscosities. For example, solvents with good solvency and low-molecular weight polymers are used to obtain low viscosity and acceptable flow in sprayable high solids coatings. 


Even 100% solids hot melt adhesives can be almost water-like in viscosity during processing at appropriate temperatures. Conversely, a gel formulation containing only 5% solids can be unpourable and behave like a semi-solid. Therefore, mixer selection is generally dictated by viscosity rather than percent solids. The starting viscosity of the solvent(s), the maximum viscosity reached by the mixture during processing and the final viscosity of the end product (if different from maximum viscosity) are all important considerations.


Jinwei Chemical Higher solid content have been achieved , "medium solids" 2K clear or pigmented .top coats for car refinishing, or pigmented coatings for high performance industrial applications are based on medium viscous  acrylic resins. Such coatings show an excellent gloss, good drying (dust free: ca 15 min., tack free: ca 3 hours), good resistance against weathering and a good chemical resistance (e.g. against gasoline, diesel, motor oil). 


Solvent choice is important for the formulation of 2K coatings with a reduced solvent content containing these low molecular polyesters, it is important to use appropriate solvents. Butyl acetate was chosen as an excellent solvent to deliver the polyester resins, because of its evaporation rate and viscosity reducing effect, and because it has a better odour than ketones - although ketones (e.g. MEK) show a larger effect in viscosity and density reduction. For the formulation of high performance low VOC lacquers, however, small amounts of further solvents (e.g. methoxy propyl acetate, xylene, solvent naptha A or butyl (di)glycol acetate) are required not only to adjust the viscosity and density, but also to achieve good levelling and degassing.