Efficient dispersing agents for pigments and fillers in aqueous systems – EDAPLAN® 49X range

Blog Archive | 10 minutes  | Author: Adam Morgan , Ph.D.

An overview of the EDAPLAN® 49X series from MÜNZING CHEMIE

If you are a formulator of aqueous pigment pastes, coatings or inks then this article will be of interest to you. The EDAPLAN® 49X series from MÜNZING CHEMIE comprises three highly efficient polymeric dispersing agents – used to obtain extremely stable dispersions of pigments and fillers. Figure 1 shows where this range sits within the context of MÜNZING CHEMIE’s dispersant portfolio; offered through Lawrence Industries in the UK and IE.

Overview of EDAPLAN dispersing agents from MUNZING CHEMIE

Figure 1. EDAPLAN® 49X grades are the universal polymeric dispersants for pigments and fillers in water borne systems.

 

Whilst it is true that no single dispersant works for ALL pigments and fillers, this range was designed to be effective on a surprisingly wide range of solids. This is particularly useful when you are working with a selection of pigments and fillers, and you don’t want to buy in lots of different dispersants. In many cases it has been demonstrated that these polymeric dispersants outperform commonly used competitor grades; in terms of colour strength, gloss, hiding power, rub-out, viscosity reduction and sedimentation resistance.

The EDAPLAN® 49X range is comprised of three dispersing agents: EDAPLAN® 490, EDAPLAN® 492 and EDAPLAN® 494. All grades are based on high molecular weight copolymers with pigment affinic groups. These bind the polymers strongly onto the surface of the pigment or filler. Pigment reflocculation is prevented through a combination of the bulky steric hinderance at the interface and, in some cases, charges on the polymer – employing the highly effective electrosteric stabilisation mechanism. An overview of the physical properties is given in Figure 2.

Physical properties of the EDAPLAN 490 series of dispersants

Figure 2. Physical properties of the EDAPLAN® 49X range of dispersing agents.

 

This article will look at which dispersants are most suitable for particular pigment/filler types however, as a general rule of thumb, you can refer to Figure 3.

Recommendations for dispersing agent by pigment type

Figure 3. Starting point recommendations for dispersing agents by pigments and filler type (in aqueous systems).

 

Some dispersing agents compromise the water sensitivity of the final film due to their ionic nature. EDAPLAN® 490 and EDAPLAN® 492 have a non-ionic structure, which results in them maintaining the water-resistance of the binder. This is evident from the tests shown below in Figure 4. In this test, a clear varnish - based on a common styrene acrylic binder combination + 5% dispersing agent - was applied to a PC-foil (12 microns wet). It was then dabbed with a water-soaked cotton wool pad after 24 hours of curing time.

Non-ionic polymer dispersing agents improve water resistance

Figure 4. EDAPLAN® 490 and 492 are based on non-ionic polymers, which results in better water-resistance of the dry film when compared to many ionically charge dispersants.

 

It must be considered that dispersants can have an impact on the König hardness of a film (Figure 5). Sometimes this can be a good thing and other times it is a factor that needs mitigating.

konig hardness variations with dispersing agent

Figure 5. Comparison of the König hardness from the films shown in Figure 4. Dispersants can have an impact on these values.

 

From a regulatory point of view, all products are VOC-free and some have various BfR and Swiss Ordinance approvals. Please contact us for more information on regulatory approvals.

If you are interested in learning more about how to optimise the dosage of dispersant on your pigment then our blog article on this topic will be useful reading.

 

Dispersing carbon black pigments in aqueous systems with the polymeric dispersing agent - EDAPLAN® 492

EDAPLAN® 492 is a high molecular weight copolymer that contains pigment affinic groups. It is carried in water at 35% active content and is VOC-free.

This dispersant is great for carbon black pigments. Inks and coatings formulated with these pigment pastes have premium gloss, colour strength and hiding power. Shock out and reflocculation are prevented when using EDAPLAN® 492 for carbon black pigment pastes. A stable and low mill base viscosity is achieved.

These points are demonstrated in Figure 6, where EDAPLAN® 492 is used to disperse and stabilise the carbon black grade - “Colour Black FW 285”. When compared with some commonly used competitor dispersants for carbon black, there is clearly a superior colour strength and rub-out performance when using EDAPLAN® 492.

 

EDAPLAN 492 dispersant results on carbon black pigment

Figure 6. Comparative performance of dispersants used in an aqueous pigment paste of Colour Black FW 285 from Orion. EDAPLAN® 492 shows excellent colour strength and rub-out performance.

 

There are many different grades of carbon black available, each with their own surface properties and particle size distributions. EDAPLAN® 492 is an excellent starting point for most of these grades and MÜNZING CHEMIE have demonstrations of such upon request. Starting point guidelines are given in Figure 7 for some commonly encountered grades of carbon black pigments.

 

guideline formulations for carbon black dispersed with edaplan 492

Figure 7. Starting point guidelines for using EDAPLAN® 492 with a selection of commonly used carbon black grades.

 

No single dispersant works for every grade of carbon black however; METOLAT® 392 and EDAPLAN® 494 might be even more effective in certain situations. What we can say is that MÜNZING CHEMIE have highly effective solutions for most cases and can work with us to find the best option. As it is system dependent, we always recommend getting in touch with the technical sales team at Lawrence Industries to find out the best option for your system.

 

EDAPLAN® 490 as a dispersing agent for organic pigments in aqueous systems

If you are looking to disperse organic pigments in waterborne systems then the two go-to products are the EDAPLAN® 490 and the 494. EDAPLAN® 490 works particularly well for azo pigments whereas EDAPLAN® 494 is generally better for laked azo pigments.

Figure 8 compares the performance of EDAPLAN® 490 on PR2, with some other commonly used dispersants. An exceptional colour strength is obtained with a much higher efficiency than the competitor grades i.e. less demand in terms of dispersant. Optimisations like this can streamline costs to make your products more competitive.

EDAPLAN 490 results on dispersing organic pigment red

Figure 8. A comparison of dispersant performance for the pigment PR2. EDAPLAN® 490 is a very efficient and effective choice.

 

Lawrence Industries has a wealth of information on dispersing organic pigments. Please contact us to discuss your project further.

 

EDAPLAN® 494 as a universal dispersing agent for titanium dioxide, organic pigments and transparent nanoscale iron oxides

EDAPLAN® 494 is one of the most universal pigment dispersants available. If you are looking to consolidate the purchasing of different dispersants into one product, then this is certainly worth evaluting.

A guideline is given in Figure 9, as to the amount of dispersant to add for different types of pigments. Performance data is available upon request.

EDAPLAN 494 universal pigment dispersant

Figure 9. Starting point recommendations for the universal dispersant EDAPLAN® 494.

 

Dispersing silica matting agents in aqueous systems with the polymeric dispersing agents - EDAPLAN® 492

Many customers matt down their systems with the ACEMATT® matting agents from Evonik. Should additional dispersant be required, then we have comprehensive data on the best grades to use.

Generally speaking, EDAPLAN® 492 works best but it depends on the particular ACEMATT® grade. An example starting point formulation for ACEMATT TS 100 would be as follows in Figure 10.

EDAPLAN 492 for dispersing silica matting agents

Figure 10. Starting point formulation for ACEMATT TS 100.

 

In conclusion

To summarise the key points from this article:

  • No single dispersant works for every pigment type, but some dispersants - such as the EDAPLAN® 494 - have excellent broad-spectrum compatibility. This allows formulators to consolidate dispersant choice to one or two grades, rather than having a different dispersing agent for each pigment.
  • See Figure 3 for a rough guideline as to which products are most suitable for the different pigment types.
  • MÜNZING CHEMIE polymeric dispersants are highly efficient at reducing mill base viscosity and stabilising against reflocculation and shock out.
  • EDAPLAN® 490 and EDAPLAN® 492 have little to no impact on water sensitivity of the dry film; due to their non-ionic structure.
  • There are a wide range of regulatory approvals to satisfy different application requirements.
  • Lawrence Industries, in partnership with MÜNZING CHEMIE, have a significant amount of experience in dispersant technology for pigment -, particularly for aqueous systems. Get in touch with our technical sales team to get the best recommendation for your project. Request a sample through the EDAPLAN® and METOLAT® dispersant home page.
Author: Adam Morgan , Ph.D.

Adam studied chemistry at the University of Warwick for 8 years, where he obtained a Ph.D. in the field of polymer and inorganic colloid science. He has been with Lawrence Industries since 2014 as a technical sales manager covering all industry areas. He is now responsible for marketing within the company as well.