Pigments and paints

Powder, slurry, paste and additive behavior in pigment and paint processing

Pigments, extenders, binders and slurries are not one category

Pigments & Paints production

Particle size, shape, surface treatment, moisture, cohesion, bulk density, agglomeration, density and electrostatic behavior decide whether a pigment or paint material flows, dusts, doses evenly, wets, disperses, or stays in suspension. This page connects what you are seeing on the line to the mechanism behind it and the measurement that settles it.

Pigments and paints

Powder, slurry, paste and additive behavior
in pigment and paint processing

Pigments, extenders, binders and slurries are not one category

Particle size, shape, surface treatment, moisture, cohesion, bulk density, agglomeration, density and electrostatic behavior decide whether a pigment or paint material flows, dusts, doses evenly, wets, disperses, or stays in suspension. This page connects what you are seeing on the line to the mechanism behind it and the measurement that settles it.

By material type icon

By material type

Organic and inorganic pigments, TiO2, fillers, binders, slurries, pastes.

By observed behavior icon

By observed behavior

Flow, caking, dust, dosing, settling, agglomeration, moisture, static.

By measurement route icon

By measurement route

The test that clearly separates one likely mechanism from another.

By process area icon

By process area

Storage, transfer, dosing, wetting, milling, letdown, filling, and recovery.

Find your route

Start with the material, then the behavior

Pigment and paint raw materials do not behave as one category. Pick the material class, then the behavior you are seeing in the process. The result names the mechanisms worth separating, the measurement to start with, and where in the process it usually shows up. It is a triage route, not a diagnosis.

  1. 1Material
  2. 2Behavior
  3. 3Route

Step 1  What are you handling?

Step 2  What are you seeing?

Step 3  Your route

Material routes

Pigment, filler, binder and additive types

The same site may handle organic pigments, inorganic oxides, titanium dioxide, carbon black, metallic flakes, extenders, resin powders, dispersants, dry color blends, waterborne slurries, solventborne pastes and recovered paint solids. Each class has its own behavior profile, so the most useful route starts with the material.

Organic pigment powder in a stainless steel sample dish

Organic pigment powders and colorants

Organic pigment powders can be cohesive, dusty, and difficult to wet. Particle size, surface treatment, and agglomeration influence feeding and dispersion.

Dust Wetting Dispersion
Inorganic oxide pigment powder in a stainless steel sample dish

Inorganic pigments and oxide powders

Inorganic pigments can be dense, abrasive, or prone to settling. Particle size, density, and surface condition affect transfer, dosing, and suspension stability.

Density Abrasion Stability
White titanium dioxide pigment powder in a stainless steel sample dish

Titanium dioxide and white pigment

Titanium dioxide grades differ in surface treatment, density, and agglomeration. These differences affect dust, wetting, dispersion, and hiding performance.

Dust Wetting Hiding
Fine carbon black pigment powder in a stainless steel sample dish

Carbon black and dark pigment powders

Carbon black and dark pigments are fine, cohesive, and highly dust-forming. Low bulk density and static can disrupt feeding, wetting, and dispersion.

Dust Static Dispersion
Metallic effect pigment flakes in a stainless steel sample dish

Effect pigments and metallic flake grades

Effect pigments and metallic flakes can align, break, or separate during handling. Shape, aspect ratio, and shear influence appearance and stability.

Orientation Shear Appearance
Light mineral extender powder in a stainless steel sample dish

Extenders, additives, and functional mineral fillers

Extenders and mineral fillers can compact, abrade, or settle. Particle size, density, moisture, and surface treatment influence dosing and rheology.

Abrasion Dosing Rheology
Solid resin binder powder in a stainless steel sample dish

Resin powders and solid binder systems

Resin powders and solid binders can soften, cake, or charge during storage and transfer. Particle size and thermal history influence feeding and incorporation.

Heat Caking Feeding
Liquid wetting agent in a stainless steel sample dish

Wetting agents and dispersant additives

Wetting agents and dispersants are added at low levels, so dosage accuracy and addition point matter more than bulk handling. Compatibility and foaming matter.

Dosage Wetting Stability
Dry color blend in a stainless steel sample dish

Dry color blends and pigment preparations

Dry color blends can be difficult to dose and disperse evenly. Cohesion, static, low addition rates, and handling variability can affect shade consistency and color uniformity between batches.

Separation Dosing Shade
Waterborne pigment slurry in a stainless steel sample dish

Waterborne concentrates and pigment slurries

Waterborne concentrates and slurries can settle, thicken, foam, or form agglomerates. Solids loading, viscosity, and dispersion state directly control overall handling stability.

Settling Viscosity Stability
Solventborne pigment paste in a stainless steel sample dish

Solventborne pastes and liquid colorants

Solventborne pastes and liquid colorants can settle, skin, or change viscosity. Solvent balance, temperature, and dispersion state directly affect transfer, stability, and formulation performance.

Viscosity Transfer Stability
Recovered paint powder in a stainless steel sample dish

Recovered paint powders and recycled solids

Recovered paint powders and recycled solids vary in size, composition, moisture, and contamination. These differences affect feeding, dispersion, and batch consistency.

Variation Feeding Reuse

Quick comparison

Material route, common risk, first measurement

The same symptom points to different mechanisms depending on the material class, formulation, and process step. This is the fast bridge between pigment and paint behavior and measurement route.

Pigment and paint material routes, the handling or processing risk each one carries most often, and the measurement worth running first.

Material routeCommon handling or processing riskUseful first measurement
Organic pigment powders and colorantsCohesion, dust release, difficult wetting, and agglomerationParticle size, bulk density, flowability, and wetting assessment
Inorganic pigments and oxide powdersHigh density, abrasion, settling, and dosing variationParticle size, density, morphology, and settling assessment
Titanium dioxide and white pigment gradesDust, agglomeration, poor wetting, and inconsistent hidingParticle size, surface condition, wetting, and dispersion trials
Carbon black and dark pigment powdersLow density, dustiness, static charging, and poor dispersionBulk density, dustiness, electrostatics, and dispersion assessment
Effect pigments and metallic flake gradesSeparation, orientation change, flake damage, and appearance variationParticle shape, aspect ratio, size, and controlled shear trials
Extenders and functional mineral fillersCompaction, abrasion, settling, and rheology variationParticle size, moisture, density, and flowability
Resin powders and solid binder systemsCaking, softening, static charging, and feeding instabilityThermal response, particle size, bulk density, and flow testing
Wetting agents and dispersant additivesAddition errors, compatibility problems, foaming, and unstable dispersionViscosity, dosage response, compatibility, and wetting trials
Dry color blends and pigment preparationsSeparation, dosing variation, dust, and inconsistent shadeComponent size, density, flow, and segregation comparison
Waterborne concentrates and pigment slurriesSettling, thickening, foaming, and agglomerate growthViscosity, solids loading, particle size, and stability testing
Solventborne pastes and liquid colorantsSettling, skinning, viscosity drift, and transfer instabilityViscosity, solvent balance, particle size, and storage trials
Recovered paint powders and recycled solidsVariable composition, contamination, moisture, and reuse inconsistencyParticle size, moisture, composition, and contamination checks

One risk per row is the one most often reported, not the only one that occurs. Use the selector above to work a specific combination through to a route.

Recurring problems

Start from the behavior you can see

These eight cover what actually gets reported in pigment and paint plants. Two of them, settling and agglomeration, replace segregation and breakage, because this industry is half liquid and those are the behaviors people report. Each one runs back to the mechanisms worth separating and forward to the measurement that confirms which one is governing.

Icon representing poor flow and discharge

Poor flow or discharge

Arching · Bridging · Discharge

Icon representing caking and consolidation

Caking or consolidation

Moisture · Load · Storage

Icon representing dust formation

Dust formation

Fines · Handling · Containment

Icon representing dosing variation

Dosing or feeding variation

Density · Refill · Feeding

Icon representing settling and separation

Settling or separation

Density · Viscosity · Stability

Icon representing agglomeration

Agglomeration

Wetting · Shear · Dispersion

Icon representing moisture sensitivity

Moisture sensitivity

Humidity · Caking · Stability

Icon representing electrostatic behavior

Electrostatic behavior

Charging · Adhesion · Buildup

Measurement routes

The test that answers your question

Pigment and paint behavior rarely resolves to one number. Particle size, surface treatment, agglomeration, moisture, cohesion, density, viscosity, wetting behavior, electrostatic behavior and dustiness can all sit behind the same visible symptom. Pick the method by the question, not by the symptom.

Feeding and transfer stability

Flowability and shear testing
Cohesion, consolidation, hopper discharge, arching, ratholing, and storage load.

Wall friction testing
Hopper design, discharge limits, wall material choice, and powder adhesion.

Wetting and dispersion

Wetting and dispersion assessment
Wetting rate, liquid demand, dispersion energy, agglomerate persistence, and foam response.

Fineness of grind
Milling response, residual agglomerates, flake damage, color development, and gloss.

Rheology and settling

Rheology and viscosity testing
Viscosity development, yield stress, settling resistance, sag, and storage stability.

Bulk and tapped density
Charge weight, aeration, compressibility, feeder behavior, and refill consistency.

Particle and morphology

Particle size distribution
Fines, agglomerates, packing, dustiness, settling, hiding power, and shade development.

Microscopy and morphology
Particle shape, surface treatment, agglomeration, flake integrity, and dispersion.

Air, dust, and electrostatics

Dustiness testing
Airborne pigment, transfer losses, dust capture, exposure, and color cross-contamination.

Electrostatic charge testing
Charging, adhesion, dust attraction, wall buildup, and unstable transfer or feeding.

Moisture and structure

Moisture content and sorption behavior
Moisture response, storage history, caking, surface change, and water-sensitive processing.

Compare every method
All test methods on the site, grouped by the question they answer.

Process routes

Where the behavior actually shows up

The same pigment or paint material behaves differently depending on where it sits in the process. Storage, transfer, dosing, wetting, dispersion, milling, letdown, filtration, filling and recovery each expose a different property and a different failure mode.

01

Storage and silos

Storage time, consolidation, moisture, temperature and electrostatic charging alter bulk density, flow behavior and later discharge consistency.

02

Powder transfer

Mechanical and pneumatic transfer can cause separation, attrition, dust release, charging, color contamination and unstable downstream feeding.

03

Dosing and feeding

Bulk density, refill behavior, cohesion, aeration, and particle shape act directly on feed rate stability, dosing accuracy, and process consistency.

04

Wetting and dispersion

Surface treatment, liquid demand, addition sequence, shear and agglomerate strength determine wetting rate and initial dispersion quality.

05

Grinding and milling

Mill type, energy input, residence time, temperature and particle strength influence deagglomeration, flake damage, color development and viscosity.

06

Letdown and blending

Addition sequence, shear history, viscosity, binder compatibility and mixing time determine uniformity, shade consistency, rheology and final stability.

07

Filtration and transfer

Agglomerates, skin, foreign matter, viscosity and pump shear influence filtration load, transfer stability, equipment fouling and final cleanliness.

08

Filling and packaging

Settling, foaming, viscosity drift, contamination and fill accuracy influence package consistency, storage stability and downstream application.

09

Drying and recovery

Drying history, residual moisture, overspray condition, contamination and particle size change influence recovery, reuse and final quality.

Go deeper

Guides and articles for pigment and paint behavior

Longer reads that work through the mechanisms behind these routes, from the visible process problem to material properties, measurement choice and interpretation.

Powder being dispersed into a liquid medium during a laboratory dispersion test

Powder dispersion, methods and data interpretation

How dispersion is achieved and measured, and why an agglomerated pigment reads very differently from a well dispersed one.

Colored concrete showing the effect of pigment dispersion on shade uniformity

Mixing effects of pigments in concrete

How pigment particle size, dispersion method and mixing protocol change color uniformity, and what that says about dispersion generally.

Powder coating being applied to a metal part in an industrial coating line

Powder coatings, applications and advantages

Where powder coatings replace liquid paint, and which powder properties decide whether the finish comes out even.

Define the powder operating window

A powder can meet specifications and still fail when humidity, consolidation, aeration, temperature, or residence time exceeds its reliable operating conditions.

Choose the test that matches the question

Flow tests answer different questions. Match the method to the process condition, stress state and failure mode instead of treating flowability as one universal property.

Know when the fine fraction takes over

A small increase in fines changes cohesion, air retention, dust formation, packing and separation even when the median particle size barely moves.

Watch moisture before visible changes appear

Moisture alters cohesion, caking, surface condition, wetting behavior, and storage stability long before anything looks visibly wet in normal handling.

FAQ

Pigment and paint material questions

The most important distinction is usually not the visible symptom itself but the mechanism behind it. Similar problems can result from cohesion, moisture, electrostatics, agglomeration, density variation, settling, viscosity, shear history, or interaction between the material and the equipment.
Behavior depends on the conditions acting on the material. Moisture, storage history, consolidation, vibration, temperature, handling, electrostatic charge, shear, and the liquid environment can all shift how the same material flows, wets, disperses, settles, or generates dust.
The useful method depends on the question being investigated. Particle size analysis may help with agglomeration or settling, while flow testing, wall friction, moisture analysis, bulk density, electrostatic testing, rheology, wetting and dispersion, or fineness of grind answer different process questions. A useful test programme starts with the suspected mechanism rather than a standard list of measurements.
Start with the information you already have. Use the material route when the pigment, filler, binder, or preparation class is known, the behavior route when a visible symptom is driving the investigation, and the measurement route when you need to decide which test can answer a specific process question.
Laboratory testing is most useful when the symptom alone does not reveal the controlling mechanism, when several causes are plausible, or when a formulation or process change needs to be evaluated before implementation. The test conditions should reflect the actual material history and process conditions as closely as practical.
Yes. A visible symptom such as unstable feeding, poor dispersion, or settling can result from several interacting factors. Combining complementary measurements can help separate effects such as moisture, cohesion, bulk density variation, particle size, surface treatment, viscosity, shear history, or electrostatic behavior.

Need the measurement, not just the guidance? PowderTechnology.info works closely with Delft Solids Solutions,
a contract research organization specializing in the physical behavior of powders and granules. DSS provides
contract testing and characterization, with its laboratory working in accordance with ISO 17025.
Contact Delft Solids Solutions.

Delft Solids Solutions logo