The 3-coat-1-bake coating system has been widely employed in automobile body painting. This study examined whether the appearance (waviness) of film can be improved by reducing difference shrinkage percentage (by weight) between primer surfacer and basecoat clearcoat after flow/leveling stops while baking. To delay time (tC) to reduce clearcoat, solventborne clearcoats were prepared blocking al...

Clearcoat filmbuild is a main concern for coating quality in automotive paint shops. In operation, a thin layer of clearcoat is sprayed on the top of other thin films on the vehicle surface and then baked in an oven for solvent removal, film topology finalization, and crosslinking reactions completion. Because of the complexity of physical and chemical phenomena occurring in operation and the l...

A computer graphic system has been developed that permits the interactive design of new automotive finishes. The software makes use of a reflection model for car paint that is based on industry standards for measuring the appearance characteristics of the paint. These measurements include gloss for the clearcoat and three aspecular measurements for the metallic basecoat. The program interface p...

The scratch resistance of coatings used on two highly visible automotive applications (automotive bodies and window glazings) were examined and reviewed. Types of damage (scratch vs. mar), the impact on customers, and the causes of scratch events were investigated. Different exterior clearcoat technologies, including UV curable and self-healing formulations were reviewed, including results from...

A novel dual-curable blocked isocyanate crosslinker was designed for the simultaneous radical and urethane crosslinking of automotive clearcoats under low-temperature conditions. Three groups on three ends hexamethylene diisocyanate-based were using two different blocking agents: a thermal initiator (TRI) dimethyl pyrazole. Clearcoats based hydroxyl-functionalized methacrylate oligomer resin hy...

Polymeric polyimide capillary tubing, both uncoated and coated with stationary phases of two polarities, is explored for use as capillary columns for gas chromatography (GC). These glass-free polyimide columns are flexible and their small winding diameter of less than a cm around a solid support makes them compatible for potential use in portable GC instruments. Polyimide columns with dimension...

The effect of different parameters including: nano silica content, curing temperature, type of hardener, and flash-off time on mechanical and optical properties of polyurethane PU based clearcoat was investigated via standard Taguchi L9 method. Dispersion of nano silica in the resultant nanocomposites was explored by scanning electron microscopy SEM. SEM images showed a fine dispersion through ...