Abstract: An ink composition and an adhesion promoter are provided. The adhesion promoter is suitable for production while remaining the stronger adhesion. The adhesion promoter is formed by the reaction of at least one alpha hydroxy acid and at least one alpha hydroxy acid ester with the metal alkoxide. More specifically, by combining the renewable and green alpha hydroxy acid and safer plasticizing alpha hydroxy acid ester as reagent to react with the metal alkoxide, the eco-friendly and non-toxic adhesion promoter with superior adhesion for use in ink composition can be obtained. The ink composition includes the adhesion promoter, a pigment, a polymeric binder, and a solvent for the polymeric binder. The ink composition is odorless and colorless, and shows good wet crinkle resistance. Especially, the ink composition is suitable for printing on the food package.

Abstract: An ink composition and an adhesion promoter are provided. The adhesion promoter is suitable for production while remaining the stronger adhesion. The adhesion promoter is formed by the reaction of at least one alpha hydroxy acid, at least one alpha hydroxy acid ester, and a polymer having hydroxyl group, amino group, carboxyl group, or a combination thereof with a metal alkoxide. By combining the renewable and green alpha hydroxy acid and safer plasticizing alpha hydroxy acid ester, and the polymer as reagents to react with the metal alkoxide, the eco-friendly and non-toxic adhesion promoter with superior adhesion for use in ink composition can be obtained. The ink composition includes the adhesion promoter, a pigment, a polymeric binder, and a solvent for the polymeric binder. The ink composition is odorless and colorless, and shows good wet crinkle resistance. Especially, the ink composition is suitable for printing on the food package.