THE EFFECT OF VARYING CONCENTRATIONS OF ARABIC GUM ON THE SOLID CONTENT OF ORGANIC INK BASED ON COCONUT SHELL CHARCOAL PIGMENT

Abstract

The development of the printing industry has increased the demand for environmentally friendly inks as
an alternative to petroleum-based inks. One potential approach is the utilization of coconut shell charcoal
as a carbon pigment source and gum arabic as a natural binder in organic ink formulations. This study
aimed to analyze the effect of varying gum arabic concentrations on the solid content of organic ink based
on coconut shell charcoal pigment. A quantitative experimental method was employed in this research.
Ink samples were formulated using two pigment bases, namely ethanol and distilled water, with gum
arabic concentrations of 1%, 3%, 5%, 7%, and 9%. Solid content testing was conducted using the
gravimetric method by drying the samples at 105°C until a constant weight was achieved. The results
indicated that increasing the concentration of gum arabic led to higher solid content values in both
pigment-base formulations. The ethanol-based samples exhibited an increase in solid content from 6.73%
to 13.61%, while the distilled water-based samples increased from 6.06% to 14.86%. The highest solid
content value was obtained in sample AT-5 containing 9% gum arabic. These findings demonstrate that
gum arabic concentration has a positive effect on the solid content of organic ink, indicating its potential
to improve ink quality in terms of solid composition and printing performance.