| 摘要 |
An aqueous, self-crosslinking 1-component (1K) polyurethane dispersion is provided to obtain acceptable viscosity, to be controllable to high solid fractions, and to exhibit excellent characteristics such as film hardness, solvent resistance, and film optical qualities in coating applications. An aqueous, self-crosslinking 1-component (1K) polyurethane dispersion has a bimodal particle size distribution, wherein a fine particle fraction[F] comprising crosslinking agent particles has an average particle size of 1-100 nm, and a coarse particle fraction[G] comprising polyurethane-polyurea particles has an average particle size of 10-400 nm. A weight ratio of the fine particle fraction to the coarse particle fraction is from 0.5/99.5 to 10/90. The dispersion has a solid content of 40-70wt%, and a viscosity of 50-20000 mPas at 23°C.
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