摘要 |
<p>An environmentally degradable cigarette filter includes a filter element of a bloomed cellulose acetate tow and a plug wrap surrounding said filter element. A weak organic acid and a pH adjusted inorganic ester salt are encapsulated in a matrix material which is in contact with the tow. The pH adjusted inorganic ester salt has a pH less than or equal to 8. When the cigarette filter is discarded into the environment, water liberates the weak acid and the ester salt from the matrix material. The weak acid hydrolyzes the ester liberating a strong acid. The strong acid catalyzes the degradation of the cellulose acetate tow. (The weak acid also hydrolyzes the cellulose acetate tow, but after the strong acid is generated, the strong acid becomes the dominant acid catalyst for the cellulose acetate tow degradation.)</p> |