KT-88540 Sparkle Bright Bronze Borosilicate Iron Oxide Pearl Pigment

The KT-88540 belongs to Kolortek's Dreamstar / Sparkle Bright line — a borosilicate-based platform distinct from standard mica pearl systems. Where mica-titanium pigments offer controlled luster, borosilicate flakes push significantly higher in brightness and transparency. The iron oxide coating on KT-88540 anchors the warm bronze color while maintaining the glass-like clarity characteristic of the substrate.

Particle size runs 40–200μm, placing this grade firmly in the coarse sparkle range. That means visible, faceted flash — not a diffuse sheen. In practice, this is the right choice when the brief calls for a bold, light-catching bronze rather than a smooth satin finish.

Series and Related Models

KT-88540 sits within the Sparkle Bright iron oxide borosilicate group. Three closely related models share the same substrate platform and particle size range, differing only in the iron oxide coating depth and resulting hue:

Worth noting: if a formulation needs a warmer, more reddish bronze tonality, KT-88542 is the logical next step in the series. For a softer, more neutral earth tone with retained sparkle, KT-88541 bridges the gap.

Key Characteristics

• Diamond-sparkle effect: Large borosilicate flakes produce a faceted, high-intensity flash — visually richer than equivalently sized mica grades.
• Unusual transparency: The synthetic glass substrate is inherently cleaner and more transparent than natural mica, allowing underlying color and substrate to remain visible while the sparkle sits on top.
• Extremely high reflection index: Borosilicate glass has a refractive index well-suited for brilliant light return, enhancing perceived brightness across viewing angles.
• Iron oxide color coat: Provides the bronze hue with good thermal and chemical stability — relevant for coatings that will see elevated cure temperatures or outdoor exposure.
• Big and smooth flake geometry: Minimizes light scattering at flake edges, contributing to the clean, sharp sparkle point characteristic of this series.
• Cosmetic compliance: Borosilicate-based pigments in this platform are used in decorative cosmetic applications. TDS, MSDS, and compliance documentation available on request.

Applications

The 40–200μm particle range defines where KT-88540 works well — and where it doesn't. Coarse sparkle grades like this are well-suited for applications where the pigment sits at or near the surface and individual flake flash is a design intent.

• Decorative cosmetics: Eye shadow, highlighter, body glitter, and bronzer formulations where large-flake sparkle is expected. The borosilicate platform is cosmetic-grade compatible.
• Nail products: Gel polish, nail lacquer, and nail art applications — the Dreamstar series is specifically noted for nail use, and this grade's coarse flake size delivers the faceted glitter-like finish common in nail aesthetics.
• Paints and decorative coatings: Architectural decorative finishes, craft paints, and specialty wall coatings where a warm bronze sparkle is part of the visual design.
• Craft and art materials: Resin art, candle coatings, and mixed-media applications where manual blending and dispersion control are manageable.

That said, this grade is not suited for fine printing inks or applications requiring a smooth, brushmark-free film. The coarse particle distribution will clog spray equipment at low tip sizes and will not pass through fine printing screens. For those end uses, finer borosilicate grades should be evaluated.

Practical Formulation Considerations

Dispersion of large-flake pearlescent pigments always carries a risk of mechanical damage. High-shear mixing — particularly prolonged ball milling or aggressive rotor-stator dispersion — will fracture the borosilicate flakes and reduce particle size, directly diminishing the sparkle effect. Low-shear stirring or gentle hand-blending is recommended for final incorporation.

In waterborne systems, check the pH tolerance of the binder matrix. Borosilicate substrates are generally more chemically stable than natural mica, but the iron oxide coating should be evaluated in highly alkaline systems before committing to production scale.

Typical loading rates for coarse sparkle effects in cosmetic or coating applications fall between 1–5% by weight, depending on the desired density of sparkle and the opacity of the base. Higher loadings are common in clear or translucent bases where the substrate allows maximum light penetration to reach each flake.

Compatibility with standard solvent-borne, waterborne, and UV-cure systems is generally straightforward. The borosilicate pigment platform does not introduce significant rheological complications at typical use levels, though viscosity should be monitored at the high end of the loading range in high-solids coatings.

How KT-88540 Compares to Mica-Based Bronze Pigments

Mica-iron oxide bronzes (such as Kolortek's KT-500 or KT-7511 Metal Luster series) deliver a warm metallic luster with strong hiding power and a smoother, more continuous sheen. They are the right choice for applications requiring a solid metallic appearance — countertops, floors, or full-coverage automotive finishes.

KT-88540 operates differently. The transparent borosilicate base means it does not conceal — it sparkles. The visual effect is more analogous to a glitter than a conventional metallic bronze coat. Both are legitimate tools; the choice depends entirely on whether the design intent is metallic coverage or diamond-flash sparkle over a visible base.

Frequently Asked Questions

Q: Is KT-88540 suitable for leave-on cosmetic products?
The borosilicate series is used in decorative cosmetic applications. For confirmed compliance with specific regional cosmetic regulations (EU, US, etc.), request the full ingredient documentation and MSDS. Kolortek provides TDS and safety data to support regulatory review.

Q: Can this pigment be used in UV-cure gel nail systems?
Yes. The Dreamstar / Sparkle Bright borosilicate series is noted for nail applications. The pigment is chemically inert relative to standard photoinitiator systems. Standard compatibility testing in the specific gel formulation is still advisable before launch.

Q: What is the difference between KT-88540, KT-88541, and KT-88542?
All three share the same calcium aluminum borosilicate substrate, particle size, and iron oxide coating chemistry. The difference is in the iron oxide coating thickness, which shifts the reflected color from bronze (KT-88540) through brown (KT-88541) to red brown (KT-88542). They can be blended to achieve intermediate tones.

Q: Is the 40–200μm range a fixed specification or can finer cuts be supplied?
The standard grade for KT-88540 is 40–200μm. For applications requiring a narrower distribution or finer particle range, contact the technical team directly — custom sizing or alternative series grades may be available depending on volume and application requirements.

Request Samples or Technical Data

Samples, TDS, MSDS, and COA for KT-88540 are available on request. For formulation support or volume pricing, reach out directly to the technical team at contact@kolortek.com.