Shimmer Pearl Mica Pigment Powder, 40–200μm – KT-163

KT-163 is a shimmer pearl natural mica pigment powder in the 40–200μm particle size range — one of the coarser grades in the KT-100 Silver White Series, designed for applications where visible, bold individual-platelet sparkle is the target effect rather than smooth coverage pearl. At this distribution, individual mica platelets coated with rutile TiO₂ are large enough to produce distinct, directional flash reflections visible to the naked eye, giving epoxy floors, countertops, decorative coatings, and craft resin applications a pronounced shimmer that finer pearl grades cannot replicate. For formulators who need a coarse silver white pearl with reliable batch-to-batch sparkle intensity, KT-163 covers the upper-brightness end of the KT-100 natural mica range.

Product Positioning

KT-163 occupies the coarse-grade end of the KT-100 Silver White Series — above the standard 10–60μm grades, the flash-range 10–100μm and 20–100μm grades, and approaching the upper limit of what natural mica-based pearl pigments can deliver in terms of individual platelet sparkle. At 40–200μm, the lower cut removes virtually all of the fine fraction that produces diffuse background pearl coverage — the visual output is dominated by individual flake reflections rather than a continuous sheen.

Within the Kolortek portfolio, KT-163 serves applications where sparkle density, depth, and visible dimensionality in the finished surface are the primary aesthetic criteria — epoxy flooring, engineered stone countertops, decorative wall finishes, and resin art. For these applications, the 40–200μm range is the standard industry specification. For applications requiring smooth film formation or fine cosmetic texture, finer KT-100 grades are the appropriate choice.

Technical Specifications

KT-100 Series: Particle Size and Visual Effect Reference

Key Technical Characteristics

Coarse platelet geometry and sparkle mechanism: At 40–200μm, each mica platelet reflects light as a distinct specular event rather than contributing to a diffuse background sheen. The effect reads as visible, moving sparkle when viewed from different angles — the larger the platelet, the more directional and brighter the individual flash. This is the same optical principle that makes coarse glitter visually distinct from fine glitter at equivalent loading levels.

Rutile TiO₂ coating — brightness and chemical stability: The rutile phase TiO₂ coating provides a refractive index of approximately 2.70, contributing to the brightness of each individual platelet reflection. Rutile also offers lower photocatalytic activity than anatase, which is relevant for epoxy floor coatings and outdoor decorative applications where UV exposure over service life is a factor. The coating is chemically stable in the neutral-to-mildly-alkaline and mildly-acidic pH range typical of most coating and resin systems.

Natural mica inclusions at coarse grades: Natural muscovite mica contains trace mineral inclusions that appear as small dark spots. At 40–200μm, individual platelets are large enough for these inclusions to be visible in finished applications when examined at close range. For applications where surface purity is a critical aesthetic requirement — prestige countertops, high-gloss display surfaces — the KT-7100 synthetic mica series (Fluorphlogopite substrate) offers significantly higher substrate purity with fewer visible inclusions at equivalent particle sizes.

Blending for silver-grey metallic effects: Adding 0.1–0.5% carbon black to a KT-163 system shifts the visual output toward a silver-grey metallic appearance — the dark background amplifies the contrast of each individual shimmer flash, increasing perceived luster intensity. Combined with aluminum paste, KT-163 adds pearlescent depth and dimensional sparkle to a flat metallic system.

Application Range

Not suitable for: printing inks, airbrush application, nail lacquer requiring smooth film, or any application with nozzle/screen specifications below 40μm. For these uses, specify fine-grade KT-100 variants with confirmed D90 below 25μm.

Formulation Notes

Mixing — coarse grades require extra care: At 40–200μm, the large mica platelets are more susceptible to fracture from mechanical shear than fine-grade equivalents. High-speed dispersers, ball mills, and tight-clearance recirculation pumps will break platelets and significantly reduce the D50, directly eliminating the shimmer character. Add KT-163 to the formulation at the letdown stage using low-shear paddle or anchor mixing only. Do not homogenize or recirculate after adding.

Settling in low-viscosity systems: Coarse mica platelets settle more rapidly than fine grades in low-viscosity liquid systems. For epoxy floors and liquid resin applications, incorporate KT-163 into the mixed resin system shortly before application — extended hold time after mixing increases settling risk. In water-based decorative coatings, rheology modifiers that suspend coarse particles (associative thickeners, fumed silica) improve distribution uniformity.

Typical loading levels: Epoxy flooring and resin applications generally use 3–10% by weight depending on desired sparkle density. Decorative wall coatings typically run 3–8%. Higher loadings increase sparkle density but do not proportionally increase per-flake intensity — once the platelet population reaches optimal surface coverage in the film, further addition adds diminishing visual return.

Kolortek has supplied coarse-grade pearlescent pigments for epoxy and decorative applications for over 20 years, with controlled particle size distribution and consistent rutile TiO₂ coating quality across production batches. TDS and SDS are available on request for KT-163. Custom coarse particle size ranges and surface treatments are available for volume buyers with specific application requirements.

Frequently Asked Questions

Q: What makes 40–200μm the standard specification for epoxy floor and countertop applications?
A: At this particle size range, individual mica platelets are large enough to produce distinct, visible sparkle events in the cured epoxy film — the effect reads as a deep, dimensional shimmer rather than a continuous satin sheen. Finer grades (10–60μm) produce a smoother, more subtle pearl that gets visually lost in the depth of a clear epoxy topcoat. Coarser grades (above 200μm) can create uneven surface profiles in thin epoxy layers. The 40–200μm range is a practical industry standard that balances visible sparkle density with processability in broadcast and integral-mix epoxy applications.

Q: Why do I see small dark spots in my finished epoxy surface when using KT-163?
A: Dark spots at the coarse grade level are typically caused by mineral inclusions in the natural mica substrate — muscovite mica contains trace amounts of iron and other minerals that appear as dark specks, which become more visible as platelet size increases. In most epoxy floor applications this is not a significant issue, but for prestige or close-inspection surfaces, the KT-7100 synthetic Fluorphlogopite series eliminates this concern through higher substrate purity.

Q: Can KT-163 be used alongside finer pearl grades in the same formulation?
A: Yes, and blending coarse and fine grades is a common technique for achieving a layered visual effect — the fine grade contributes continuous background pearl coverage while the coarse grade adds pronounced individual sparkle points on top. A typical starting blend would be 70% fine grade (10–60μm) plus 30% KT-163 — adjust the ratio based on the target balance between background coverage and sparkle prominence. Both grades can be added at the letdown stage using the same low-shear mixing protocol.

Q: Is KT-163 suitable for outdoor coating applications?
A: The rutile TiO₂ coating on KT-163 provides better UV stability than anatase-coated equivalents — rutile's lower photocatalytic activity reduces degradation of organic binder systems under UV exposure. For industrial pearlescent pigment applications, natural mica-based grades generally perform adequately in architectural coatings with protective topcoats. For demanding outdoor applications requiring long-term weatherfastness, the KT-7100 synthetic mica series offers better weathering resistance due to the higher chemical purity of the Fluorphlogopite substrate.

Request Samples or Technical Data

Shimmer sparkle character in epoxy and decorative applications is best evaluated in your specific system — resin type, film thickness, and application method all affect how the 40–200μm platelet distribution reads in the finished surface. Contact Kolortek to request a sample of KT-163, download the TDS with particle size distribution data, or discuss grade selection across the KT-100 Silver White Series for your application.