Background / Context:
Through vivid colors, nature communicates and inspires human beings. Colors bring meaning to life. Technological advances in painting have resulted in man substantially overtaking nature in terms of coloring efficacy. Painting owes its feasibility and viability to organic solvents. These solvents evaporate during the curing period, emitting Volatile Organic Compounds (VOC) which are harmful to flora and fauna.
Though most of the paints are converted into water based solutions, global experts in automotive paints are unable to realize clear coat into water based solution. Clearcoat in any vehicle is indispensable as it is one of the important factors which determines the sale of the vehicle. Clear coat is still with organic solvents so related hazard is carried forward.
We undertook the challenge of development of a water-based solution for clearcoat on automotive bodies. Unavailability of a ready solution, passion for stopping health hazard for painting technicians and harmful effects on ecology inspired us to innovate this solution.
After numerous experiments with applications, formulations and blends, we found an industry first, most optimal way to apply the clearcoat on to vehicle, normally the realm of only solvent based coats.
Water as a solvent in paint system has inherent problems. By virtue of limitation in self-crosslinking polymer technologies and challenges in reduction of co-solvent content, dry film may have low gloss value, poor hardness and scratch resistivity. Study and experiments were carried to understand the morphologies and crosslinking mechanisms that are effective to realize the waterborne clear coats. Good water dispensability and stability achieved through new dispersing technologies that allow for minimal hydrophilic modifications or consume all or part of the hydrophilic groups. Formulation is derived so that polymer design is optimized to achieve maximum adhesion and crosslinking. Careful choice of other formulation components, contribute to reduced solvent demand while maintaining acceptable rheology. We have designed new process for baking and flash off system. Flash off time is increased to 25-30 min between base coat and 1 st clear and to 15 to 20 min between two clearcoats. Baking is done after 25 to 30 min of application of last clearcoat. Baking cycle is changed to 75-850 C for 30-40 min.
We have created a waterborne paint formulation which is capable of meeting the stringent requirements of the Automotive Industry. A unique formulation of desired parameters gives the intended results in any climatic conditions. We have successfully taken the trials and proved the results. Ingredients of this paints are easily available and final product can be produced easily. Paint application process is simplified and standardized so that it can easily adopted by end user.
As per records 92 million vehicles are produced per year globally. Along with exterior body, 25% of vehicles interior plastic parts and 100 % of vehicle haptics can adopt this inventive step instead of solvent base paints. This can be deployed to toy industry and wood industry as applicable. Thereby in all, Waterborne clear coat can replace solvent based clear coat