Polyurethane products from ALPA

ALPA SpA, the Italian leather chemical manufacturers, have introduced a series of polyurethane based finishing compounds. RPU F 95 is a polyurethane in a water emulsion which has been designed to be used as a final top coat for glossy finishes, particularly with leathergoods leathers. The anionic white liquid may also be used on upholstery leathers. RPU F 95 can be used with resin or casein finishes as an additive to a final ironable top coat. When used in combination with RPU 075 and NEA 212, this product is catalysed to provide a finish with high wet and dry rubfastness with a strong resistance to water spot swelling. RPU F 95 forms a strong transparent and glossy film. After fixation with crosslinkers Alparet and Alparet ISO, the finish achieves high physical fastness properties. Akral PU 262 is an anionic viscous opalescent liquid polyurethane product in a water dispersion. This product has been designed to be applied by rollercoater and is particularly suitable for finishing split leathers. The thick polyurethane has strong physical fastness properties with excellent covering power. Akral PU 262 provides a dull appearance, good embossing properties without stickiness. Akral PU 262 should be applied only with a pigment in quantities between 15-20% by rollercoater and if diluted, can be added by spray finishing. Splits should be buffed with 220 AWB paper or haircell embossed using the following recipe: 800 Akral PU 262 200 Lustratop Mix Pigment Pass twice with a 17G roller, Rotopress, then pass through twice more with the 17G roller. The finish should be followed by a NEA nitro emulsion and a fixative top coat. This product has a solids content of 35% and a pH of 9.0 in a 10% solution. Akral PU 25 is a 'charged' ready-to-use compound based on acrylic and polyurethane resins, which is particularly suitable for brush-off or college type finishes. The anionic, medium viscous opalescent liquid forms a soft and elastic film with excellent covering characteristics and high mechanical resistance to wet and dry flexometer testing. Akral PU 25 may also be used in ground coat primers as an additive to improve covering and does not cause looseness. This product is usually applied by rollercoater as it has a good spreading effect and a homogeneous film. The product should be added alone or with a pigment and the following recipe is suggested: 800 Akral PU 25 200 Lustratop Mix Pigment Rollercoat twice with a 25G roller, Rotopress followed by two more passes with 25G roller and finally apply a top coat according to the type of finish required. Akral PU 25 can also be sprayed as a ground coat, for example, diluted 1-1.5 in water thus making spraying easier and improving coverage. This product has a solids content of 30% and a pH of 9.0 in a 10% solution. Akral PU 26 is similar to Akral PU 25 and is also a ready-to-use acrylic and polyurethanic base compound suitable for brush-off or college type finishes. It is also an anionic opalescent medium viscous liquid, which forms a medium dull film. It can also be used as a ground coat for patent top coats. Akral PU 26 has good covering and spreading properties and is non-sticking when used in the ironing operation. This product is applied by rollercoater and maybe added with a pigment (4:1) or if a particularly dull finish is required, matt fillers SFT MV3 or SFT MV4 should be added. Due to its great elasticity, a film made with Akral PU 26 provides strong mechanical resistances to wet and dry fastness. This product has the same dry content and pH as Akral PU 25.