Studies on effect of pigment and binder combinations on surface

The present work attempts to analyze the surface and physical properties of leathers finished with various combinations of binders and pigments by keeping other auxiliaries constant. The contact angles of liquid drops resting on the leather surface have been used to evaluate surface energy, acidity, basicity components of the surface energy, polarity and work of adhesion. Contact angle values have been measured for chrome tanned and conventionally re-tanned crust and finished leather made by varying pigment and binder combinations. The wettability of finished leather has been correlated with the contact angle values: the higher the contact angle value the less wetting is observed. Complete wetting can be obtained when the contact angle value is zero i.e. the drop of liquid spread spontaneously on the surface and partial wetting is obtained when the contact angle value is in between 00 and 90o. Acrylic binders with different film forming properties, protein, polyurethane and butadiene binders have been combined to prepare different finish formulations.