Photochromic dye molecules undergo a reversible structural change when struck by UV light in the 300–360 nm range. In the absence of UV, the molecules remain colorless. Exposure to sunlight or a black light shifts the molecular structure, causing the dye to absorb visible light and produce color. When the UV source is removed, the molecules revert to their original state and the color fades.

The ink activates to full, intense color in approximately 15 seconds of direct sun or UV light exposure. When brought back indoors away from UV, the color fully fades back to clear in approximately 5 minutes. Fade speed is also influenced by ambient temperature — cooler conditions may slow the return to colorless.

The standard photochromic materials are fully reversible and can cycle thousands of times between colorless and colored states. SpotSee also offers an irreversible solvent-based screen ink and label format that permanently changes from clear to color after a single UV exposure — useful for tamper-evidence or one-time UV exposure confirmation.

SpotSee photochromic materials are available as: Plastisol Inks for textile screen printing, pigment powders and microencapsulated slurries for aqueous and non-aqueous systems, dyes for direct solubilization into materials, and Masterbatch pellets for plastic injection molding and extrusion. Each format is engineered for its specific manufacturing process.

16 standard colors are available across the ink and plastisol lines: Aqua, Brown, Charcoal, Cyan, Dark Blue, Gold, Green, Magenta, Orange, Pink, Plum, Purple, Red, Rose, Turquoise, and Yellow. Pigment powders and slurries are offered in 6 standard CMY-based colors. The system supports a 4-color CMYK process for full-spectrum printing. Custom colors are available on request.

Plastisol Ink is specifically formulated for screen printing onto textiles and similar substrates using a PVC-based carrier system. Standard Photochromic Ink uses a water- or solvent-based system suited for a broader range of print processes including paper, glass, ceramics, and plastics. Both activate under the same UV conditions and share the same 16-color palette.

 Masterbatch comes in pellet form and is dosed into plastic resin during injection molding or extrusion. The photochromic pigment becomes embedded throughout the plastic matrix. Color change intensity increases with material thickness — thicker plastic walls produce a more pronounced color shift upon UV activation.

SpotSee photochromic materials are compatible with textiles and apparel, glassware, ceramics, plastics, paper, and coatings. Plastisol inks bond to fabrics; pigment powders and slurries integrate into water- and solvent-based coating systems; dyes solubilize directly into inks and resins; and masterbatch pellets compound into molded or extruded plastic products.

Yes. Custom UV spectrum triggers are available, allowing SpotSee to engineer formulations that activate at specific UV wavelengths beyond the standard 300–360 nm sunlight range. This is useful for black light-only applications, controlled industrial UV environments, or security printing where activation should only occur under a specific light source.

Yes. Photochromic materials can be combined with permanent pigments or dyes to create a two-state color effect — for example, a material that is blue indoors from the permanent pigment and shifts to a different color outdoors when the photochromic activates. This enables layered, multi-state color-change designs in a single application.

Yes — the inks and plastisol formulations are washable without chlorine. Chlorine-based bleaches or detergents should be avoided as they degrade the photochromic compounds. Standard non-chlorine laundering preserves the color-change performance across repeated wash cycles in textile applications.

Applications include apparel and novelty textiles, hidden message reveals on game pieces and packaging, UV exposure alert labels, cosmetics and personal care packaging, glassware and ceramic decoration, security printing, plastic toy and product manufacturing, sunglass and ophthalmic lens coatings, and industrial UV-indicator labels.

The photochromic compounds used are non-toxic in standard formulations. As with any specialty ink or pigment, specific safety data sheets (SDS) should be reviewed for the intended application — particularly for direct skin contact, food-contact surfaces, or children’s products. Contact SpotSee for SDS documentation tailored to the specific format being used.