RHEOBYK-420 is a liquid rheology additive for aqueous and water-reducible coating systems, designed to improve anti-sagging and anti-settling properties. It is especially suited for manufacturing aqueous pigment concentrates and causes thixotropic flow behavior. Post-addition is possible.

Chemical Family: Urea & Urea Derivatives

Physical Form: Liquid

Features: Anti-Settling, Easy Handling, Good Leveling, High Shear Thinning, Highly Thixotropic, Improves Anti-Sagging Properties, Low Viscosity, Syneresis Resistance

Enhanced TDS

Identification & Functionality

Features & Benefits

Applications & Uses

Application Area
Coating End Applications
Industrial Additives End Use
Use Level
0.3 - 1.5% (Coatings Industry - Prevent Settling), 0.3 - 3% (Coatings Industry - Prevent Sagging)
Application Information

Coatings Industry
Special Features and Benefits

After being stirred into the coating system, the additive generates a three-dimensional network structure. The resulting thixotropic flow behavior is highly suited for preventing sedimentation and syneresis and increasing the anti-sagging properties without impairing leveling. The additive is liquid and therefore easy to handle. It is not necessary to specifically adjust the pH value or control the temperature during incorporation.
Recommended Use
RHEOBYK-420 is preferably used as an anti-settling additive to produce aqueous pigment, filler and matting agent concentrates. The additive's excellent shear thinning effect is advantageous for dosing such concentrates because of their low viscosity. In addition it is suitable for controlling the thixotropic flow behavior and to optimize the anti-sagging properties and leveling.

Recommended Levels
0.3-1.5% additive (as supplied) based on the total formulation to prevent settling.
0.3-3% additive (as supplied) based on the total formulation to prevent sagging.
The above recommended levels can be used for orientation. Optimal levels are determined through a series of laboratory tests.
Incorporation and Processing Instructions
Addition into the millbase ensures optimum distribution and therefore the best possible effectiveness and reproducibility in applications. It is not necessary to specifically control the temperature or adjust the pH value. The additive is suitable for adjusting the viscosity afterwards by incorporating it as a post-additive. If the use as a post-additive causes the product to appear non-homogeneous, typical co-solvents can be used to improve the homogeneity.
Special Note
As the additive contains chloride ions, we recommend testing the corrosion properties of the manufactured coatings for contact with metal and to store the coatings in plastic containers or containers with interior coating to prevent corrosion in metal containers. In the cured coating, however, no negative impact on its corrosion protection has been found.

Properties

Physical Form
Typical Properties
ValueUnitsTest Method / Conditions
Density (at 20°C)1.12g/ml-
Active Substance52%-
Flash Point95.0°C-
Solventn - Methylpyrrolidon--
SDS Physical and Chemical Properties
ValueUnitsTest Method / Conditions
Lower Explosion Limit1.3%V
Upper Explosion Limit9.5%V
Auto Ignition Tempertauremin. 200°CM0062, Analytics Wesel
Flash Point95°CPensky-Martens
Initial Boiling Point203°CDerived
Melting Pointmax. 0°CDerived
Density (at 20°C)1.12g/cm³Oscillating U-tube
Vapour Pressure (at 20°C)max. 1hPaDerived
AppearanceLiquid--
ColorLight yellow--
Flammability (liquids)Sustains Combustion--
Miscible inWater--
pH (at 20°C, Concentration: 10%)5-Universal pH-Value Indicator
Note

We recommend using RHEOBYK-410 for medium and RHEOBYK-411 for low-polarity, non-aqueous systems.

Composition

Solution of a modified urea

Regulatory & Compliance

OEM Specifications

Storage & Handling

Storage Conditions

Moisture sensitive. Store dry. Slight turbidity of the material that occurs during storage has no influence on the rheological effectiveness. The specified storage stability upon dispatch applies when the product is handled correctly and stored in unopened original containers.