To provide a velvet-tone leather-like sheet having excellent appearance, touch and physical properties, and a method for producing the sheet using an aqueous polyurethane dispersion free from organic solvents.
The velvet-tone leather-like sheet is composed mainly of ultrafine fibers having a single fiber fineness of ≤0.5 dtex and a binder B. The binder contains at least 2 kinds of binders A and B having different distribution in the thickness direction of the sheet. The production method for the sheet contains the steps (1) to (4). (1) A step to form a substrate by using a fiber forming ultrafine fibers of ≤0.5 dtex by the treatment with an alkaline aqueous solution, (2) a step to apply an aqueous dispersion of the binder A to the substrate and dry the dispersion with hot air, (3) a step to treat the substrate with an alkaline aqueous solution to form ultrafine fibers and (4) a step to apply an aqueous dispersion of the binder B having a heat-sensitive gelling temperature of ≤80°C to the substrate and heat the product with steam and/or microwave to the heat-sensitive gelling temperature or above.
WATANABE KOJI
HORIGUCHI TOMOYUKI