Polyurethane System for Wood

I have worked on direct to glass coatings which are majorly 2K polyurethane monocoat pigmented as well as clear finishes. Very few applications are with 1K acrylic finishes which are used for fast drying and economical purpose.

Here 2K PU glass coat is based on pure acrylic polyol resin which needs aliphatic polyisocyanate for curing reaction. Usage of complete aliphatic chemistry makes this system UV resistant. So it can be used for exteriors as well.

Most of the market follows the trend of back printed glass coat for aesthetic purpose. So the coatings should be very fast drying and should achieve early hardness development so that it can be stick to wall claddings or panel boards using adhesives.

Selection of resin and the adhesion promoter will dictate the performance of the glass coating.

Roughly the combined RMC of 2K PU Clear Glass Coat (Wide Gloss Range) will be in the range of Rs. 145-160/ltr^a and for pigmented RMC will be in the range of (Rs. 190-220/ltr) depending on the solid colour.

a = Raw Material cost includes the basic raw material coasting of both base and hardener along with packing cost and freight.

The final cost of product will depend on the consumption of OEM customer but any margin to company less than 50% is not agreeable. We have compared and tested our developed glass coat (1K and 2K both) with the market standard i.e. SABOO Coatings and Premium Coatings which covers a huge network area nearby Delhi, Punjab and Moradabad. Our glass coat performed much better in terms of performance and the customer had cost benefits also by working with us.

Similarly 1K acrylic clear as well as pigmented glass coat was developed using TPA beads. This was purely aliphatic in nature and thus was UV resistant. Chemical performances like stain and detergent resistant was not good as compared to 2K systems but it is less costly and dries very fast. So the applicator will have advantage in his production efficiency.

RMC/ltr for clear would be around Rs. 85-90/ltr and for pigmented Rs. 130-155/ltr.

Glass coating can be clear or pigmented. But in pigmented, it can be solid colour/translucent colour finish/metallic shades/special effect like mirror finish, crackle effect, multicolour finish and thousand stripes.

In metallic glass coating, most important to look out for is the orientation of the metallic particle and the covering versus percentage addition so that the cost should not be a factor. Translucent colour glass coatings can be achieved using dye based stains.

Lastly the special effects like mirror finish is based on very fine particle size aluminium silver paste which after addition of 10-15% in glass coating gives mirror lookalike. In Multicolour glass coat finish is developed by mixing different-different pre-coated coloured granules in unspecified proportions to form a multicolour finish. The system should be incompatible with these pre-coated colour granules so that it should not get mixed into each other. Thousand stripes glass coat finish is developed using very high molecular weight and extremely fast drying polyester resin which comes in thread like structure when applied by particular spray gun system. Now crackle effect is basically a two coat system and is based on the technique of incompatibility of coated and uncoated silica particles.

All Metallic, Special Effect and Translucent colour glass coat finishes are based on the customer requirement. So RMC is different for different application criteria. We haven’t compared such coatings with any Market standard.

W ood Softwood Pine, Cedar, Fir and etc.