High pH value Pigment Concentrates

Regulation of biocides is getting more & more challenging for many coating applications. Aqueous formulations with high pH values offer an option to avoid microbial growth without the addition of biocides in the formulation – but pH values of approximately 11 leads to significant challenges with regards to stability of e.g. pigment concentrates. Coating Additives offers a variety of wetting & dispersing additives for such systems.

High pH-values - an opportunity to avoid biocides

One possibility to formulate biocide-free colorants is to increase the pH-value
At a pH-values greater than 11.0, bacteria and fungi cannot grow
pH-values higher than 11.5 must be labelled „corrosive“, so the goal is to maintain a stable pH value in the desired range
Challenges:
- stable pH-value over time
- stable viscosity
- stable coloristic properties

Options for aqueous wetting & dispersing additives which contain no intentionally added biocide

Options for 100% active matter Wetting & Dispersing additives for water-based systems

pH adjustment: Amino alcohols are a valid option to achieve stable pH in the desired range

Formulation of PR 101 concentrate:

Water	33.5
TEGO® Dispers 750 W	15.0
TEGO® Foamex 26	1
AEROSIL® 200	0.5
BAYFERROX® 120 M	50
AMP 90	adjust pH to 11.5
12% additive solid on pigment

High pH value pigment concentrates with AMP 90 – Recommendation for inorganic pigments

Formulation of PR 101 concentrate:

Water	33.5
Wetting & dispersing additive, 40% active matter	15.0
TEGO® Foamex 26	1
AEROSIL® 200	0.5
BAYFERROX® 120 M	50
AMP 90	adjust pH to 11.5
12% additive solid on pigment

High pH value pigment concentrates with AMP 90 – Recommendation for organic pigments

Formulation of PV 23 concentrate:

Water	33.9
Wetting & Dispersing Additive, 40% active matter	25.0
TEGO® Foamex 26	1
HOSTAPERM® Violet RL special	40
AMP 90	adjust pH to 11.5
25% additive solid on pigment