Waterborne polyurethane and preparation method thereof, and waterborne scratch-off ink and preparation method thereof

Abstract

Provided are a waterborne polyurethane (WPU) and a preparation method thereof, and a waterborne scratch-off ink and a preparation method thereof. A chain end group or side group of the WPU contains a longer alkyl chain. When the WPU is used in the preparation of the waterborne scratch-off ink, microphase separation may occur during the film-forming process owing to a hydrophobic/hydrophilic interaction between the non-polar long-chain alkyl and polar groups in WPU molecular, resulting in an incomplete film structure, which is beneficial to make the ink be scratched off.

Dependencies are inferred from the claim text.