Architectural coating means a coating recommended for application to stationary structures and their appurtenances, portable buildings, pavements, curbs, fields and lawns. It is well known that most exterior coatings and many interior coatings require additives to prevent the growth of micro-organism on the surface. Formulation ingredients of emulsion paints are good nutrients, especially the low molecular weight hydrophilic additives such as thickeners and surfactants. The extent of colonisation by different organisms varies according to substrate (wood or plaster) and the prevailing conditions (temperature, substrate pH, humidity and light intensity), but under the right circumstances fungal and algae growth can cause massive defacement of exterior surface. 

Luckily, there are number of chemical solutions to the problem and a range of fungicides and algaecides have been identified that can be incorporated into paints and plaster to provide a measure of protection from microbial attack. These are called Biocides. They are commonly added to paint formulations to maintain the product’s integrity from microbial attack and to provide protection in the dry film against any fungal and algal growth. Most paint consumers expect the aesthetic look of their painted surface to last for a long time. Microbial growth often stains paints and deteriorates paint properties. Biocides for dry film protection play a large role in maintaining paint’s physical beauty and keep any microbial growth away from the coated surface. One such efficient biocide which has dual property of fungicide as well as algaecide in paint formulation is Kumar organic’s Kopthione Zn 40% FPS. 

The chemical name of Kopthione Zn 40% FPS is Zinc Pyrithione 40% FPS. It is available in fine dispersion form. It is stable in extremely low particle size aqueous dispersion for complete protection of all type of paints from microbial attack. Kopthione 40% FPS has low solubility in water; this property makes it ideal for all types of architectural (indoor and outdoor) paints. Kopthione 40% FPS is effective against wide range of bacteria, fungi and algae which grows on walls. The antifungal effect of Kopthione 40% is derived from its ability to disrupt membrane transport by blocking pump that energizes the transport mechanism. Kopthione 40% FPS also prevents discoloration of paint by protecting buildings from decomposition by UV light of direct sunlight.

Hence we can say Kopthione Zn 40% has a proven track record as a commercial antimicrobial agent and possesses all the key features of a paint film fungicide/algaecide including broad spectrum activity (fungi & algae), low aqueous solubility, ease of formulation and ability to deliver long lasting protection. Also, given the small number of active ingredients currently available, zinc pyrithione is worth investing for film protection in paint formulation.