Viability of organic sources as a sustainable highlighter pen ink

Highlighter pens have been essential tools for students, instructors, and office employees for many years. They are used to emphasize specific information in written texts, making it easier to recognize, remember, and retrieve later. This study proposed the use of organic sources to create solvent-based highlighter pen ink. Specifically, it aimed to determine the viability of using organic sources such as Annatto seeds and blue butterfly pea as sustainable highlighter pen ink and to assess if there was a significant difference between the physical properties of commercial and organic highlighters. An experimental research design was applied, wherein the researchers produced two concentrations of ink and observed which concentration was suitable as highlighter pen ink. The study involved forty (40) students from the College of Education at Laguna University who tested the organic highlighters in one day and answered a validated questionnaire. The results revealed that Annatto seed highlighter pen ink exhibited a more intense color, while blue butterfly pea highlighter pen ink had a mild odor. As a result, respondents strongly agreed on the physical properties of the two organic sources as highlighter pen ink. However, both organic sources resulted in show-through, meaning that the ink could be seen through to the other side, usually due to thin paper or bold ink. Additionally, the study showed that both Annatto seed and blue butterfly pea highlighters were acceptable. However, Annatto seed highlighter was preferred due to its better ink qualities. The research also indicated that there was no significant difference between the physical properties of commercial and organic highlighters, suggesting that highlighter pens made from organic sources can be used as sustainable alternatives. The researchers encouraged further investigation into the advantages of using natural inks derived from organic sources in ecologically friendly and sustainable production methods. This study opens possibilities for utilizing organic materials as alternatives to traditional highlighter pen inks, contributing to environmentally conscious practices in the stationery industry.