LAYERED MATERIAL AND METHOD FOR PRODUCING A LAYERED MATERIAL

摘要

The invention relates to a method for producing a surface-structured layered material which has a backing layer (1) and a polyurethane layer (2) connected thereto, the backing layer (1) used, in particular in pieces, being a leather, preferably a smoothed full-grain leather or a split cowskin, a textile material, preferably a woven fabric or a knitted fabric, a cellulose fibre material, a split foam, a leather fibre material or a microfibre fleece and being connected to the layer (2), and the layer (2) applied to the backing layer (1) being at least one, preferably a single layer formed of a PU foam, in particular containing gas pockets, preferably a whipped PU foam optionally containing hollow microspheres and/or a PU foam containing hollow microspheres. According to the invention: - the PU foam, in particular containing gas pockets, is created with a PU dispersion mixture, wherein the individual PU dispersions used to create the PU dispersion mixture exhibit different softening points in the dry state; - to create the PU dispersion mixture, one or more PU dispersions having heat-activatable melting and contact adhesive properties and a softening point in the dry state greater than 40°C, preferably greater than 45°C, in an amount of 18 to 52 wt% of the finished PU dispersion mixture is/are mixed with one or more PU dispersions without melting and contact adhesive properties and with a softening point greater than 95°C, preferably greater than 125°C, in an amount of 39 to 73 wt% of the finished PU dispersion mixture; - the PU dispersion mixture for the layer (2) is applied to the backing layer (1) with a thickness such that the layer has a thickness in the dried state of 0.075 to 0.450 mm, preferably 0.150 to 0.280 mm; - before or during structuring of the PU foam, a further layer (3) of a non-foamed PU dispersion which is a mixture of multiple PU dispersions is applied to the layer (2); - the backing layer (1) is optionally cut or punched into blanks or pattern parts before or after the application of the PU foam, in particular after the drying thereof, and the coated blanks or pattern parts are subjected to stamping or structuring under pressure and temperature; and - the backing layer (1), the further layer (3) and the layer (2) are compressed and joined to one another and structured with a die (4) under application of a contact pressure of 4 to 48 kg/cm2, preferably 4 to 48 kg/cm², in particular 18 to 25 kg/cm².