Finishing solutions from Fenice16 March 2003
Italian finishing chemical specialists, Fenice, have introduced a binder, a prebottom and an intermediate. All the products should be stored between 5-40ºC and have a shelf life of at least six months. The details of each of the new products are as follows: Lifting is a polyurethane binder made from natural and synthetic fillers in a water dispersion. It is a buffable prebottoming compound for corrected grain and split leathers. It has excellent sealing and surface levelling as it covers small defects. It gives the leather a uniform appearance, which is full and round. Lifting also prepares the leather for subsequent finishing coats. This product forms a rubbery, elastic and matt film. It has been formulated in such a way that the tanner or finisher has to add between 15-20% of water. This allows for the viscosity to be regulated and any remaining amounts of Lifting already diluted may give rise to surface layers, so care should be taken and stirring carried out before use. For masking larger defects, Fenice recommend other products such as Mender or Hider. The application of Lifting allows an increase in leather quality, but even if the surface film obtained is technically good, it could affect the flexing endurance. Therefore, Fenice recommend that the tanner should carry out some specific preliminary tests before adoption. Lifting is a viscous white fluid and a 1:10 solution has a pH of 9.0. The dry content and density of this product are 22% and 0.73g/cm3 respectively. It should be applied by rollercoater with a viscosity of 20'' Ford Cup N.6. Apply 60-80g/sq m and after application dry plate at 80ºC, 100 atm and buff with paper 240. ROD is modified aliphatic polyurethane in a water dispersion. It is an alternative to nitro-emulsions and is a completely solvent-free intermediate insulator used for embossed leathers. When applied on the prebottomings before embossing/plating operations, it gives excellent insulation and a good releasing efficiency without compromising its overspraying ability and adhesion. For example, use 100 parts of ROD with 300 parts of water and apply 50g/ sq m. It is a white emulsion with a dry content of 15% and a density of 1.0g/cm3. The pH of a 1:10 solution is approximately 7.5. Mirror is a modified protein binder in a water solution. It produces an elastic and glossy film, which is not thermoplastic. It has a wide range of uses in all protein or polymeric films that have to be heat resistant and bright. When applied to leathers for shoe upper, slippers or boots, the characteristics of Mirror can be seen. It is resistant to hot ironing, heat setting, ironing at very high temperatures and has excellent glazability. For glazed leathers, Mirror may be used in lower coats, whereas for final bright tops it is preferable to use harder, less soft and elastic binders such as DC 250 from Fenice. A further application for Mirror is that of a promoter of adhesion in pre-bottoming and basecoats with or without only very small quantities of polymer resin in the formulation. As a prebottoming compound it should be sprayed diluted with water in a ratio of 1:3 or 1:5 then plated or polished. Repolishability will also be increased in this case. Mirror is yellowish viscous liquid and has a dry content of 14%. The pH of a 1:10 solution is approximately 8.5 and it has a density of about 1.02g/cm3. Typical example of use for Mirror as a polishable basecoat can been seen in Table 1.