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Crystal Violet lactone (CVL) is a colorless lactone derivative of crystal violet. The CVL compound contains two dimethylaniline groups attached via a tetrahedral carbon atom to 6-dimethylaminophthalide at the third position.
C 8456 (OTTO) Crystal violet lactone, dye content, 97% Cas 1552-42-7 - use in color-changing printing. It serves as a reversible color system with temperature change.