Glycolic acid has unique features for inkjet inks, lithographic inks, and fountain solutions.
Glycolic acid is an alpha hydroxy acid featured with dual functional groups in its structure. The combination of hydroxylic and carboxylic groups allows it to function as a penetrant, chelating agent, or buffering agent, depending on your ink-formulating needs.
Glycolic acid, CAS number 79-14-1, may be used in inks as an additive at sufficient concentrations to allow for the pH-sensitive bleed control mechanism to be effective. The presence of organic acids, such as glycolic, greatly improves the wetting of inkjet ink in solid block areas, thus preventing the ink from coalescing onto itself, resulting in even surface distribution of ink.
CHEMOURS GLYCOLIC ACID BENEFITS
Improved Descaling Efficiency
Glycolic acid counteracts the effects of dissolved calcium from hard water and prevents scale from reacting with the ingredients of inks or fountain solutions. It can easily replace EDTA in a formulation.
Improved Bleed Control
Glycolic acid reduces bleed and enhances wetting, flow, and gloss. It also helps absorb titanium dioxide and enables better suspension and fixation of inks onto the substrate. It acts as a penetrant by penetrating the substrate vertically, decreasing the lateral spreading of the ink. Glycolic acid allows for uniform area fills and improved color quality while maximizing light-fastness without sacrificing print reliability using any conventional technique.
Glycolic acid does not boil at high temperatures like other organic acids. It is an effective organic acid in inkjet inks, especially when formulated with pH-sensitive colorants to inhibit color migration.
Provides pH Stability
Glycolic acid can be used as a primary or secondary acid in a fountain solution, which also acts as a buffering agent to maintain constant pH throughout the formulation.
GLYCOLIC ACID PROPERTIES COMPARED TO OTHER ACIDS
|Properties||Glycolic Acid||Acetic Acid||Citric Acid||Phosphoric Acid||EDTA|
|Solubility in Hard Water|
|Solubility in Acidic Media||✔||✔||✔||✔||✔|
|Low Molecular Weight||✔||✔||✔||✔||✔|
|Odor||Mild Low Odor||Strong Pungent||Odorless||Odorless||N/A|
✔ - Excellent
✔ - Good
✔ - Poor