# Scientists Develop Futuristic PhotoTat Ink Visible Only Under UV Light New switchable ink technology allows tattoos to appear and disappear using light exposure. - **Source:** [Science & tech Articles | Mail Online](https://www.dailymail.com?ns_mchannel=rss&ns_campaign=1490&ito=1490) - **Published:** 2026-11-02 - **Topic:** [Business](https://brifing.si/c/business) - **Original article:** - **On Brifing:** https://brifing.si/s/bc5e1807-7af9-466a-b598-d2c3a8794bc5 ## Innovative PhotoTat Ink Technology Researchers at the University of Colorado Boulder have engineered PhotoTat, a novel ink that remains invisible until exposed to UV light. The technology utilizes polymethyl methacrylate (PMMA) spheres injected with color-changing dyes. These microscopic spheres function like a switch, allowing users to reveal or hide their tattoos based on specific light environments. ## Mechanism of Visual Control The ink responds dynamically to external light sources. When a UV flashlight is applied, the tattoo becomes visible for several hours. Conversely, exposure to bright LED light triggers a deactivation process, rendering the ink invisible again. Lead author Carson Bruns demonstrated this on his own leg, featuring fish scales that glow red, orange, and blue. ## Current Safety and Toxicity Hurdles PhotoTat has not yet received approval for human use, limiting its current application to experimental settings. Miriam O'Duill of the University of Nottingham highlights significant challenges, including the blue ink's tendency to degrade after 10 to 100 activations. This degradation leaves behind a permanent, purple-colored mark, necessitating extensive safety and toxicity testing before commercialization. ## Environmental Sensitivity Concerns The ink's stability remains a primary concern for potential users. Direct sunlight contains sufficient UV radiation to inadvertently activate the tattoos unless protected by sunscreen. Furthermore, indoor ambient light can cause the colors to slowly fade over several days. These environmental factors complicate the goal of a reliable, long-term "day-to-night" aesthetic transition. ## Alternative Painless Tattoo Developments The sector is seeing rapid innovation, evidenced by UK-based startup CipherX. They developed a painless tattoo system using disposable patches covered in hundreds of tiny spikes. These microneedles deposit carbon-based ink into the skin without traditional tattoo guns. The process is bloodless, causes minimal tissue damage, and currently costs only £50 per design. ## Historical Context of Tattoos Tattooing has a deep history, exemplified by the 5,000-year-old mummy Ötzi, discovered in 1991. Researchers identified 61 distinct tattoos on his body using specialized light wavelengths. These markings, dating to 3250 BC, are considered the oldest known tattoos, potentially serving therapeutic purposes like acupuncture to alleviate chronic joint or chest pain. ## Evolution of Figurative Art Beyond geometric patterns, figurative tattoos have been identified on 5,000-year-old Egyptian mummies at the British Museum. These markings depict wild bulls and Barbary sheep, pushing the timeline for figurative body art back by 1,000 years. Such discoveries transform our understanding of ancient social practices and the symbolic significance of permanent skin modifications. ## Future of Skin Modification The convergence of advanced material science and historical tattooing practices signals a shift in body modification technology. While PhotoTat offers a futuristic, reversible solution, it must overcome durability and safety barriers. As research progresses, the integration of light-responsive materials may eventually redefine how individuals express their identity through temporary, high-tech skin art. ## Sources covering this story - https://www.dailymail.com/sciencetech/article-16258309/tattoo-INVISIBLE-ink-revealed-UV-flashlight.html?ns_mchannel=rss&ns_campaign=1490&ito=1490 — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._