AQUEOUS POLYURETHANE DISPERSION

• Main Authors: HASSEL TILLMANN DR, MUENZMAY THOMAS DR, MEIXNER JUERGEN DR, REINERS JUERGEN DR, SCHOOB JOERG
• Format: Patent
• Language: English
• Published: 25.05.2000
• Edition: 7
• Subjects: ADHESIVES; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; APPARATUS THEREFOR; APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL; CHEMICAL PAINT OR INK REMOVERS; CHEMICAL TREATMENT OF HIDES, SKINS OR LEATHER, e.g. TANNING,IMPREGNATING, FINISHING; CHEMISTRY; COATING COMPOSITIONS, e.g. PAINTS, VARNISHES ORLACQUERS; COMPOSITIONS BASED THEREON; COMPOSITIONS FOR TANNING; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; CORRECTING FLUIDS; DYES; FILLING PASTES; GENERAL PROCESSES OF COMPOUNDING; HIDES; INKS; LEATHER; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; ORGANIC MACROMOLECULAR COMPOUNDS; PAINTS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; PELTS; PERFORMING OPERATIONS; POLISHES; PROCESSES FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TOSURFACES, IN GENERAL; SKINS; SPRAYING OR ATOMISING IN GENERAL; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; USE OF MATERIALS THEREFOR; WOODSTAINS; WORKING-UP

PURPOSE: An aqueous polyurethane dispersion is provided which gives coating materials which have excellent wet abrasion fastness and high wet and dry flexural durability. CONSTITUTION: An aqueous polyurethane dispersion comprises a) at least one polyol having number -average molecular weight of 500 - 6000 g/mol, preferably 1000 - 4000 g/mol, more preferably 1500 - 3000 g/mol; b) at least one polyol, preferably diol having molecular weight of less than 500 g/mol, preferably 61 - 499 g/mol; c) at least one aliphatic polyisocyanate, preferably diisocyanate; d) at least one diol having molecular weight of less than 450 g/mol and containing at least one ionic group and/or potentially ionic group, preferably at least one carboxyl group or carboxyl acid salt group; e) at least one amine having 1 - 6 OH group and reactive to NCO group; f) water, and optionally g) primary alcohol, wherein the molar ratio of polyol a) to the sum of polyols b) and d) is 1: 1.5 - 1: 4, preferably 1: 2 - 1: 3, the molar ratio of the sum of polyols a), b) and d) to polyisocyanate c) is 1: 1.1 - 1: 2.5, preferably 1: 1.2 - 1: 1.7, the number of OH group of polyurethane is preferably 2 - 6, more preferably 2 - 4, and number-average molecular weight of polyurethane is less than 15000, preferably 2500 - 10000, particularly 3000 - 7000 g/mol.