RESIN 4 is a special re-tanning for chrome leathers .Its particular tanning action allows to obtain a full leather, without to change thinness of the grain. It is viscous but it is a good pourable and it is easy to dilute with hot water. The product is sensitive to the acids and with data of ph less than 3 it can dash; it can be mixed only with cationic products ( for example Mineral tanning ). RESIN 4 don’t give problem if it is used in the usually concentration with synthetic and vegetable tanning, fat licker, sulfitated, anionic dyes and others anion active products, if the PH don’t fall under limit values . RESIN 4 gives fullness at the leathers in the re-tanning, without to injure thinness and firmness of grain, and it acts without to alter the typical character of the chrome leather, also if they need again of synthetic vegetable retanning. RESIN 4 is solid at the light and it gives uniform dyes and slightly clear. It gives at the skins an high white color together white tanning.