Particle Size and Stability Analysis for Paints, Inks and Coatings Coatings, Paints & Inks
Color strength, opacity, gloss, flow behavior, surface finish and shelf life all depend on how particles behave within a paint, ink or coating formulation. Pigments, fillers, binders and functional additives must be carefully characterized to prevent agglomeration, settling, inconsistent application and visible defects in the final film.
MICROTRAC provides particle characterization technologies for dry powders, concentrated dispersions, nanoscale ingredients, coating sprays and finished formulations. By measuring particle size, shape, surface properties, charge and physical stability, formulators and quality-control teams can identify the material causes of performance variation and make better-informed formulation and process decisions.
From raw-material qualification and milling optimization to stability testing and final-product quality control, particle size analysis for paints and coatings helps manufacturers improve consistency, shorten development cycles and achieve more reliable product performance.
Connect Particle Properties with Coating Performance
Paint formulation particle analysis helps manufacturers understand how pigments, fillers and other dispersed materials influence both processing and final coating quality.
- Controlling color strength, hiding power, opacity and gloss
- Detecting agglomerates and evaluating pigment dispersion efficiency
- Optimizing milling, blending and formulation conditions
- Comparing dispersants, surfactants and stabilizer concentrations
- Improving flow, leveling and film uniformity
- Preventing settling, flocculation and phase separation
- Controlling powder-coating fluidization and deposition
- Optimizing droplet size in spray and inkjet applications
MICROTRAC instruments provide complementary measurements for these challenges, allowing users to select the analytical approach that best matches their material, formulation and application process.
Pigment Particle Size Analysis for Reliable Color and Appearance
Pigment particle size strongly influences how light interacts with a coating. Changes in particle size distribution can affect color strength, opacity, hiding power, gloss and the appearance of the finished surface. Oversized particles and agglomerates may also create defects, reduce dispersion quality and cause inconsistent results between production batches.
Laser diffraction provides fast and repeatable particle size distribution measurements for pigments, fillers and other coating ingredients. It can be used during raw-material inspection, milling and dispersion development, as well as for routine production quality control.
Measure Particle Size and Shape with SYNC
The MICROTRAC SYNC combines laser diffraction with dynamic image analysis in a single instrument. This dual-technology approach measures particle size while also providing visual and quantitative information about particle shape and agglomeration.
- Monitor pigment and filler particle size distributions
- Detect oversized particles and agglomerates
- Evaluate changes during milling or dispersion
- Compare incoming raw-material batches
- Investigate variations in gloss, opacity or surface appearance
- Characterize liquid and dry samples across a broad size range
Combining size distribution data with particle images helps distinguish individual particles from agglomerates and provides more context than particle size results alone. This is particularly valuable when materials with similar size distributions produce different formulation or application behavior.
Fine Particles, Nano-Additives and Ink Particle Size
Advanced coatings and inks increasingly contain submicron and nano-particles, fine pigments, functional additives and colloidal ingredients. These materials can influence optical performance, conductivity (for conductive inks), barrier properties, durability and other specialized functions, but their behavior depends on maintaining a controlled particle size and a stable dispersion.
Dynamic light scattering extends particle size analysis into the submicron and nanometer range, making it suitable for fine dispersions that cannot be fully characterized using conventional methods for larger particles.
Analyze Nanoscale Ingredients with NANOTRAC FLEX
The MICROTRAC NANOTRAC FLEX uses dynamic light scattering to measure colloidal and nanoscale particles in inks, coatings and pigment dispersions. Its unique probe design and Laser Amplified Detection enable fast, accurate measurements directly in almost any sample, even at high concentrations and without prior dilution.
- Nano-additives used in functional coatings
- Fine organic and inorganic pigments
- Ink and inkjet formulations
- Colloidal binders and coating ingredients
- Functionalized or surface-treated particles
- Changes in particle size caused by aggregation
NANOTRAC FLEX helps formulation teams determine whether fine particles remain adequately dispersed and whether processing or storage conditions are causing particle growth or agglomeration. The resulting data can support raw-material selection, dispersion optimization and troubleshooting when a formulation no longer delivers the expected optical or application properties.
Powder Coating, Pigments and Functional Materials Particle Size and Shape Analysis
Coating performance depends on more than average particle size. The full particle size distribution and morphology influence key properties such as fluidization, transport, charging, dispersion behavior, packing, surface coverage and the final appearance of the coating. An excessive proportion of fine particles may create handling or recovery challenges, while oversized particles can lead to uneven deposition and surface defects. Particle shape is equally critical – especially for pigments, flakes, extenders and other non-spherical materials – as it affects viscosity, orientation and overall coating performance. Parameters such as aspect ratio, circularity and particle width help explain differences between materials with similar nominal sizes, while also revealing agglomerates, deformed particles and inconsistencies.
Characterize Powder Size and Shape with CAMSIZER
MICROTRAC CAMSIZER instruments use dynamic image analysis to measure particle size and shape rapidly and objectively. Their high-resolution optical system analyzes thousands of particles per second, delivering statistically robust results and reliable detection of even small fractions of oversized or irregular particles. They quantify parameters such as aspect ratio, roundness and particle dimensions while identifying agglomerates and out-of-specification particles.
- Particle size distribution control
- Detection of oversize particles and agglomerates
- Evaluation of particle morphology
- Comparison of production batches
- Milling, classification and blending optimization
Because every measured particle is evaluated as an image, dynamic image analysis provides detailed information about the actual morphology of a powder. This allows users to identify shape-related differences that may not be visible in a size distribution alone.
Ink and paint Particle Size and Zeta Potential
Particle size results are most valuable when they are interpreted together with the forces acting between dispersed particles. A formulation may contain particles of the correct size immediately after processing but still become unstable during storage if the particles attract one another and form flocs or aggregates.
Zeta potential provides information about the electrostatic interactions surrounding dispersed particles. It can help formulators evaluate whether repulsive forces are sufficient to keep particles separated and compare the effect of dispersants, surfactants, pH adjustments and other formulation changes.
Optimize Dispersants with STABINO ZETA
The STABINO ZETA uses streaming potential technology to measure zeta potential across a wide sample concentration range. Its patented oscillating piston design enables fast, repeatable measurements directly in concentrated suspensions, minimizing sample preparation and preserving real formulation conditions. Measurements can be performed without the extensive dilution that may alter the original behavior of concentrated pigments and inks.
- Evaluation of pigment and ink dispersion zeta potential
- Comparison of dispersants and surfactants
- Optimization of stabilizer dosage
- Investigation of component interactions
- Charge titration and formulation screening
- Troubleshooting of aggregation and flocculation
- Analysis of aqueous and solvent-based systems
Rapid feedback allows formulation teams to identify the conditions that provide effective particle stabilization. This can reduce trial-and-error development and help prevent color variation, viscosity changes and application problems associated with an unstable dispersion.
Coating Dispersion Stability Testing and Shelf-Life Prediction
Settling, creaming, clarification, flocculation and phase separation can reduce the value of a coating long before it reaches the end user. Traditional shelf-life testing often relies on visual inspection and extended storage, meaning that instability may only be detected after weeks or months.
Visual observation also provides limited information about when instability begins or which physical mechanism is responsible.
Detect Instability Earlier with TURBISCAN
The MICROTRAC TURBISCAN range uses static multiple light scattering to monitor physical changes throughout a sample without relying only on visual assessment.
By detecting changes before they become visible, TURBISCAN helps formulators compare candidate formulations more quickly and conduct accelerated stability studies. In suitable applications, differences that would otherwise require prolonged storage can be identified within hours or days.
- Migration such as: sedimentation, creaming, clarification
- Changes in particle size: flocculation, aggregation, coalescence…
- Phase separation
- Packing and redispersibility behavior
- Faster formulation screening
- Earlier identification of unstable products
- More objective comparison of stabilizers and dispersants
- Shorter development and troubleshooting cycles
- Improved confidence in storage and transport performance
- Reduced dependence on subjective visual evaluations
TURBISCAN is particularly useful for concentrated pigment dispersions, inks, emulsions and formulations that should not be diluted before analysis.
Surface Area and Porosity in Specialty Coatings
Surface area and pore structure influence how powders interact with binders, solvents and other formulation components. These properties may affect liquid demand, adsorption, drying, coverage and the mechanical behavior of the finished layer.
Surface area and porosity measurements are especially useful for porous fillers, adsorbent materials, functional pigments and specialty coatings designed for filtration, catalysis, protection or controlled interaction with the surrounding environment.
Evaluate Surface Properties with BELSORP
The MICROTRAC BELSORP series uses gas adsorption techniques to characterize specific surface area and pore structure.
- Compare the surface area of pigments and fillers
- Characterize porous coating ingredients
- Investigate pigment-binder and filler-binder interactions
- Evaluate adsorption capacity and liquid demand
- Support the development of functional or porous coating layers
- Identify raw-material differences that affect formulation behavior
This information complements particle size analysis by showing how much surface is available for interaction within the formulation.
Spray Droplet Size for Coating and Ink Application
The performance of a liquid coating depends not only on the formulation itself but also on how it is atomized and applied. Droplet size distribution influences coverage, transfer, film thickness, surface uniformity and material consumption.
Changes to the nozzle, pressure, formulation viscosity or operating conditions can alter the spray pattern and lead to overspray, inconsistent film formation or unnecessary waste.
Optimize Atomization with AEROTRAC II
The MICROTRAC AEROTRAC II provides real-time spray and droplet size measurements for coating and ink application processes.
- Compare spray nozzles and atomization conditions
- Monitor droplet size distribution
- Investigate changes caused by formulation adjustments
- Improve coating coverage and film uniformity
- Reduce overspray and material waste
- Support spray-painting and inkjet process development
Real-time analysis allows development and process teams to connect operating conditions directly with droplet behavior at the point of application.
Choose the Right Particle Characterization Approach
Different coating challenges require different measurements. MICROTRAC offers complementary technologies that cover materials from nanoscale dispersions to dry powders and application sprays.
For routine pigment, filler and coating-powder size distributions, with additional images and shape information.
For fine particles, nano-additives, colloidal dispersions and nanoscale inks.
For detailed powder size, morphology, agglomerate and oversize-particle analysis.
For the surface area and pore structure of pigments, fillers and porous coating materials.
For optimizing dispersants, surfactants and electrostatic stabilization.
For monitoring settling, clarification, flocculation, phase separation and redispersibility.
For real-time droplet size measurement during spray and inkjet application.
Combining these techniques gives formulators a clearer understanding of how raw-material properties, dispersion conditions and application parameters influence final coating performance.
Key Applications in Coatings, Paints and Inks
- Pigment and filler size and shape analysis
- Paint formulation particle analysis
- Powder coating particle size analysis
- Nanoparticle and functional-additive characterization
- Ink particle size and zeta potential measurement
- Dispersant and surfactant optimization
- Quality control of dispersions and suspensions
- Accelerated coating dispersion stability testing
- Shelf-life and redispersibility evaluation
- Surface area and porosity analysis
- Spray droplet and atomization optimization
Application Notes and Technical Resources
Explore practical examples of particle characterization in coating, paint and ink workflows. Select an application-note title below to open the linked PDF.
Metallic Effect Pigments
The combination of Laser Diffraction and Dynamic Imaging with the SYNC analyzer provides more comprehensive characterization of metal effect pigments than ever before.
Ink: Measurement of Particle Size and Zeta Potential
An application note about size and zeta potential measurement of high-concentration inks with Nanotrac Wave II.
Characterizing high concentration pigments and inks
An Application Note describing the analysis of particle size and zeta potential of inks in pigment dispersions at high concentration.
Solve a Coating Formulation or Quality-Control Challenge
Whether the issue is pigment agglomeration, inconsistent color, powder-coating variation, dispersion instability or spray performance, MICROTRAC instruments help connect measurable particle properties with real formulation and production outcomes.
Share your sample and measurement objective with a MICROTRAC specialist to identify the most appropriate analytical approach.
