loader image

K-1 Hollow Glass Microspheres

Ultra-Low Density Lightweight Filler for Advanced Material Systems

K-1 Hollow Glass Microspheres are ultra-lightweight, thin-walled, closed-cell (hermetic) spherical glass particles engineered to deliver maximum weight reduction (lightweighting) in a wide range of construction, polymer, composite and specialty material applications. Manufactured from soda-lime borosilicate glass, K-1 microspheres combine exceptionally low true (particle) density with narrow particle size distribution (PSD), enabling significant density reduction while maintaining rheological stability and formulation robustness.

Owing to their high sphericity and isotropic morphology, K-1 Hollow Glass Microspheres act as rheology modifiers that improve powder flowability, reduce apparent viscosity, and minimize yield stress build-up, allowing higher volumetric filler loading versus conventional mineral fillers. They are chemically inert, non-combustible, and exhibit high hydrolytic/alkaline resistance, making them broadly compatible with cementitious matrices, thermoset and thermoplastic resins, coatings, adhesives, and sealants. K-1 is particularly suited for systems where extreme density reduction, thermal insulation (lower effective thermal conductivity), and processing efficiency (improved mixing, pumping, and application) are critical.

Applications

Polyester Putty & Body Fillers

Used in automotive and industrial polyester putties to achieve significant weight reduction, low shrinkage, easy sanding and smooth surface finish while maintaining mechanical strength.

Thermal Insulation Coatings

Ideal for thermal barrier and insulating coatings, where the hollow structure lowers thermal conductivity, improves energy efficiency and reduces coating density.

Adhesives

Suitable for structural and non-structural adhesives, providing volume build, controlled viscosity, improved spreadability and reduced formulation weight.

Sealants

Used in PU, MS polymer, silicone and hybrid sealants to enhance gap filling, sag resistance, dimensional stability and lightweighting without compromising adhesion.

Sandable Coatings & Surface Fillers

Incorporated into sandable coatings, primers and surface fillers to improve thickness build, sanding ease, surface smoothness and application efficiency.

Gelling Agents & Rheology-Modified Systems

Used in formulations requiring controlled viscosity and thixotropy, supporting stable gel formation while minimizing weight addition.

Mining Explosives

Widely used in bulk emulsion explosives and ANFO formulations for density control, improved pumpability, stable explosive emulsions and optimized energy distribution during blasting operations.

Lightweight Concrete & Cementitious Systems

Applied in lightweight concrete, grouts, mortars and repair compounds to reduce dead load, improve workability and enhance thermal insulation.

Underbody Plastisol & Automotive Coatings

Used in automotive underbody plastisols to reduce weight, improve thickness build, stone-chip resistance and NVH performance.

Properties

Property Typical Value
Appearance White, free-flowing powder
True Density ~0.125 g/cc
Crush Strength (Isostatic) ~250 psi
Average Particle Size (D50) ~65 µm
Top Cut Particle Size ~120 µm
Chemical Composition Soda-lime borosilicate glass
Shape Hollow spherical
Solubility Insoluble in water
Combustibility Non-combustible

Benefits

Maximum Weight Reduction for lightweight formulations

Improved Flow & Processability due to spherical geometry

Lower Resin, Binder & Cement Demand

Enhanced Thermal Insulation Performance

Reduced Shrinkage & Improved Dimensional Stability

Better Surface Finish & Easier Sanding in putties and fillers

Chemical Inertness ensuring long-term stability

Optimized Cost-to-Performance Ratio in volume-driven applications

Safety & Hazards

K-1 Hollow Glass Microspheres are considered non-hazardous under normal industrial handling conditions. Avoid generating excessive airborne dust. Use appropriate personal protective equipment such as safety glasses, gloves and dust masks during handling and processing. Always refer to the latest Safety Data Sheet (SDS) for detailed safety information.

Storage & Handling Guidelines

Store in a cool, dry and well-ventilated area, away from moisture and direct sunlight. Keep containers tightly closed when not in use to prevent contamination and moisture ingress.

Packaging Information

Small Box 20 kg

K-1 Hollow Glass Microspheres are ultra-lightweight, thin-walled, closed-cell (hermetic) spherical glass particles engineered to deliver maximum weight reduction (lightweighting) in a wide range
K-15 Hollow Glass Microspheres are low-density, hollow spherical glass particles engineered to provide an optimal balance between weight reduction and mechanical strength.
K-37 Hollow Glass Microspheres are medium-density, hollow spherical glass particles designed to deliver an excellent balance of mechanical strength, durability and weight reduction
S28HS Hollow Glass Microspheres are high-strength, hollow spherical glass particles engineered for applications that demand superior mechanical integrity, pressure resistance and long-term durability
iM16K Hollow Glass Microspheres are very high-strength, hollow spherical glass particles engineered for applications exposed to extreme pressure, high mechanical stress.
iM30K Hollow Glass Microspheres are ultra-high strength, hollow spherical glass particles engineered for the most extreme pressure, load-bearing and mechanically demanding applications.
3M™ Glass Bubbles XLD3000 are ultra-low density, high-strength hollow glass microspheres manufactured from water-resistant and chemically stable soda-lime borosilicate glass.