Preparation method of waterborne polyurethane base cloth and waterborne polyurethane base cloth product

Abstract

The invention relates to a preparation method of waterborne polyurethane base cloth and a waterborne polyurethane base cloth product. The preparation method comprises the following steps of (1) impregnating a sea-island fiber non-woven fabric into waterborne polyurethane slurry, wherein the dynamic viscosity of the waterborne polyurethane slurry is greater than or equal to 300 mPa.S; (2) taking out and continuously soaking the fabric in an electrolyte solution; (3) performing cleaning with hot water with the temperature of 65-100 DEG C; (4) performing freezing treatment; and (5) performing drying at the temperature of 100-130 DEG C to obtain the waterborne polyurethane base cloth. The prepared waterborne polyurethane base cloth is decreased and dried to obtain waterborne polyurethane microfiber leather; and under the condition that the diameter of a test ring is 20 mm, the softness of the waterborne polyurethane microfiber leather is 3-7. According to the method disclosed by the invention, a waterborne polyurethane emulsion is used for replacing solvent type polyurethane resin, so that the environmental pollution is greatly reduced, a solvent recovery device is not needed, the equipment investment and the energy consumption are reduced, and the prepared leather has a relatively fine foam structure, is full in hand feeling and rich in elasticity and is similar to real leather.

Description

technical field [0001] The invention belongs to the technical field of polyurethane microfiber leather production, and relates to a preparation method of water-based polyurethane base cloth and products thereof. Background technique [0002] As the latest generation of synthetic leather products, microfiber synthetic leather is a composite material composed of microfiber and polyurethane. It is one of the ideal substitute materials for genuine leather. Widely used in many fields such as sofas, clothing, shoes, automobiles, bags, etc., it is the main direction of the development of synthetic leather technology. [0003] At present, most domestic superfine fiber synthetic leathers use solvent-based polyurethane impregnated with superfine fiber non-woven fabrics, and in DMF-H 2 O solution is solidified to form polyurethane micropores, and then through the processes of water washing, weight reduction, drying, and post-finishing, the superfine fiber synthetic leather base cloth ...

AI Technical Summary

Problems solved by technology

However, mechanical foaming has high process requirements (it takes a long time to stabilize the foam, and the life of the foam after the foam is stabilized is short), the cell structure is difficult to control, and the cost is high (the solid content of water-based polyurethane needs to be greater than 50%, and the foam stabilizer needs to be added. agent, foam stabilizer and other additives), and at the same time, some bubbles will be filtered out by the sea-island non-woven fabric during impregnation, which is difficult to control; chemical foaming currently has no foaming agent suitable for water-based polyurethane systems; adding water-based polyurethane emulsion The polymer can be extracted / decomposed, the cost is greatly increased and the viscosity-increasing process is unstable. The incomplete extraction / decomposition will cause the base fabric to feel hard and not flexible enough. It will also add impurities to the subsequent recycling process, increasing the difficulty and cost of recycling.

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