PE(聚乙烯)与 PE 袋在印刷以后,在印刷图案的周围往往会有发黄现象,并且在图案背面也有,这就有可能转移到内在的包装物上。特别是在钛白色的不透明薄膜上,这个缺陷尤为显著,在未经印刷的 PE 薄膜上这种现象也时有发生。PE 薄膜发黄现象是一种化学作用,这是其中的酚基衍生物氧化作用而引起的,或者在生产 PE 粒子时,把不纯的酚基材料放进通常使用的化合物里面引起的。通常使用 PE and PE bags tend to yellow around the printed image after printing and are also present on the back of the pattern, making it possible to transfer to the inner package. This defect is especially noticeable on titanium white opaque films, a phenomenon which has often occurred on unprinted PE films. Yellowing of the PE film is a chemical reaction caused by the oxidation of the phenol-based derivative thereof or the impure phenolic-based material introduced into commonly used compounds in the production of PE particles. Commonly used