color shifting ink
/ˈkʌlə ˈʃɪftɪŋ ˈɪŋk/
n
English · color shifting ink中文 · 防伪油墨Español · tinta de color cambianteFrançais · encre à couleur changeante
意味：A feature to prevent counterfeiting; a special ink is used that changes color when viewed from various angles.