Yellow Green Zinc Sulfide Glow in the Dark Pigment, 20–40μm – KT-GYG03DSA

Yellow Green Zinc Sulfide Glow in the Dark Pigment, 20–40μm – KT-GYG03DSA

Special Effect Pigments › Glow in Dark Pigment Series › Zinc Sulfide

KT-GYG03DSA is a Yellow Green zinc sulfide (ZnS) phosphorescent pigment in the 20–40μm particle size range — the cost-effective glow-in-the-dark option in the Kolortek range for applications where a short-duration afterglow is functionally sufficient and the price premium of strontium aluminate is not warranted. Zinc sulfide glow pigments have a long commercial history in toys, novelty items, and low-cost decorative products where the glow function is a feature rather than a safety-critical performance specification. KT-GYG03DSA delivers yellow-green glow — the same color as the peak-efficiency strontium aluminate grade — at a lower unit cost and with the different performance profile characteristic of ZnS chemistry.

Zinc Sulfide vs. Strontium Aluminate — Understanding the Trade-Off

The choice between zinc sulfide and strontium aluminate glow pigments is a performance-versus-cost decision, not simply a price comparison. The two phosphor chemistries differ in three practically important ways:

For applications where overnight glow or safety-level afterglow performance is required, specify KT-GYG03 SC (strontium aluminate, 12–25μm). For decorative and novelty applications where a brief glow effect is functionally sufficient, KT-GYG03DSA is the cost-appropriate specification.

Technical Specifications

Key Technical Characteristics

Faster charge, shorter glow — the ZnS performance profile: Zinc sulfide phosphors reach near-peak brightness quickly under light exposure — shorter charging times produce visible glow. The trade-off is that the energy is also released quickly: glow brightness drops off significantly within the first 30 minutes and useful visible glow typically ends within 1–2 hours. For products used in short dark-exposure contexts — novelty items that go from light to dark for a few minutes, briefly darkened rooms, glow products for young children's play — this short-duration profile is functionally adequate. For applications requiring glow through a full night, the 1–2 hour profile is not sufficient, and strontium aluminate is the appropriate specification.

20–40μm — medium particle size for coating and craft applications: At 20–40μm, individual ZnS particles are not typically visible as discrete points in standard coating film thicknesses, producing a fairly uniform diffuse glow. This particle size suits screen printing inks (confirm against mesh specification), coating applications, and craft products where smooth surface finish is preferred. For plastics compounding, the 20–40μm range disperses adequately in most thermoplastic matrices at standard processing temperatures.

Moisture tolerance relative to strontium aluminate: Zinc sulfide is less sensitive to moisture than strontium aluminate — while it is still not recommended for direct incorporation into aqueous systems without protective treatment, it tolerates mildly humid processing conditions better than untreated SrAl grades. For formulations where complete moisture exclusion is difficult to maintain, ZnS offers a practical processing advantage over untreated strontium aluminate, though performance in the final product should still be confirmed by bench testing.

Kolortek supplies both zinc sulfide and strontium aluminate glow pigments across multiple particle sizes and glow colors — a practical advantage for formulators who need to evaluate both chemistries from a single supplier with consistent documentation standards. TDS and SDS are available on request for KT-GYG03DSA.

Application Range

Frequently Asked Questions

Q: When should I choose KT-GYG03DSA zinc sulfide over KT-GYG03 SC strontium aluminate?
A: Choose KT-GYG03DSA when the product requires a glow feature rather than a glow function — novelty items, toys, craft products, and decorative applications where brief glow lasting 30–60 minutes is sufficient and cost reduction is a material specification objective. Choose KT-GYG03 SC strontium aluminate when afterglow duration and brightness are functional requirements — safety marking, emergency guidance, fishing products, or any application where users depend on sustained glow performance. The two grades are not interchangeable for performance-dependent applications.

Q: Can KT-GYG03DSA be used in water-based systems?
A: Zinc sulfide is more moisture-tolerant than untreated strontium aluminate, but it is not formulated specifically for waterborne systems. In mildly aqueous conditions — short contact time, neutral pH — ZnS shows better stability than untreated SrAl. For water-based coating systems where the pigment will be in prolonged contact with water, bench testing of afterglow performance before and after water exposure is recommended before production specification. For dedicated waterborne-compatible grades, Kolortek's water-based glow series (30–50μm, surface-treated strontium aluminate) is the appropriate alternative.

Q: Does KT-GYG03DSA contain radioactive materials?
A: No. KT-GYG03DSA is a non-radioactive zinc sulfide phosphorescent pigment activated by copper or similar rare earth dopants. Historical glow-in-the-dark products used radium, but all modern commercial phosphorescent pigments — both zinc sulfide and strontium aluminate — are non-radioactive photoluminescent materials that store and release energy from visible and UV light only.

Request Samples or Technical Data

If you are evaluating glow pigment options for a cost-sensitive application, Kolortek can supply samples of both KT-GYG03DSA zinc sulfide and KT-GYG03 SC strontium aluminate for direct comparison in your formulation and application conditions. Contact Kolortek to request samples, download the TDS, or discuss which grade fits your performance and cost requirements.