noticias de la compañía sobre UV LED: The Invisible Hand of Artifact Restorers

In the field of cultural relic restoration, "minimal intervention" and "reversible restoration" are core principles. Traditional restoration methods are often limited by problems such as heat damage, chemical residues, and insufficient precision. A UV LED manufacturer, in collaboration with a top domestic cultural relic protection research institute, has customized and developed a low-temperature precision UV LED curing system to address two major challenges: repairing cracks in bronze artifacts and reinforcing ancient paper. This system has successfully solved the restoration difficulties of many precious cultural relics and has become a model for the application of technology in niche fields.

This restoration involved two typical types of cultural relics: First, a Western Han Dynasty bronze phoenix lamp, buried underground for over two thousand years, exhibited numerous fine cracks ranging from 0.1 to 0.3 mm. In some areas, the bronze body and rust layer had peeled away. Traditional epoxy resin curing requires high-temperature heating, which could easily cause the decorations to fall off. Second, a rare Ming Dynasty book, whose paper had become fibrous due to insect infestation, with fiber strength reduced to only 30% of the original paper. Conventional paste reinforcement could easily cause water stains and require a drying period of up to 72 hours, jeopardizing the safety of the relic. "The thermal sensitivity of bronzes and the fragility of ancient books have created a 'reinforcement inevitably leads to damage' dilemma in the restoration work," said Li, a restorer at the Institute of Cultural Relics Protection. He added that a "heat-free, residue-free, and precisely controllable" curing technology is urgently needed to break this deadlock.

To address the specific needs of cultural relic restoration, UV LED manufacturers have developed customized solutions, with core breakthroughs in three key areas: light source design, adhesive compatibility, and operation control.

Utilizing a 365nm/395nm dual-band adjustable cold light source, and employing an aluminum nitride ceramic substrate and distributed heat dissipation structure, the temperature rise in the irradiated area is kept below 5℃, completely eliminating heat radiation damage to the cultural relics. The power density is infinitely adjustable between 5-500mW/cm², and combined with an optical lens group, the spot diameter is precisely controlled between 0.5-10mm, enabling focused repair of minute cracks in bronze artifacts as well as coverage of specific reinforcement areas in ancient books.

A custom-designed UV-curing adhesive for cultural relics was developed in collaboration with adhesive companies: For bronzes, the adhesive's refractive index matches the bronze corrosion layer (1.52-1.55), achieving a cured strength of 25 MPa and allowing for reverse dissolution with a special solvent, meeting the requirements for reversible restoration; for ancient books, a nano-cellulose-modified UV adhesive is used, with a viscosity of only 5 mPa·s and a controllable penetration depth within 0.01 mm. After curing, it forms a "network cross-link" with paper fibers and is completely transparent with no fluorescent residue.

Equipped with a microscopic imaging and laser positioning module, the system allows for 200x magnification of the restoration area for real-time observation. Curing parameters are preset via a touchscreen—bronze crack repair uses a "365nm wavelength + 100mW/cm² power + 2-second curing" mode, while ancient book reinforcement uses a "395nm wavelength + 50mW/cm² power +

Pre-treatment Stage: The surface of the crack was cleaned with an ethanol mixture to remove loose rust and contaminants. The crack depth was confirmed through non-destructive testing (maximum 1.2mm).

Adhesive Injection and Curing: Customized UV adhesive was injected into the crack using a micro-syringe. The UV LED spot was aligned with the injection area using laser positioning, and curing was initiated according to preset parameters. The adhesive cured within 2 seconds, and no adhesive overflow was observed during the process using a microscopic system.

Post-treatment: The surface of the cured adhesive layer was polished with fine sandpaper. Combined with traditional antiquing techniques, the color and texture of the repaired area were made completely consistent with the original artifact. X-ray fluorescence spectroscopy showed no abnormal chemical residues.

Fiber Reinforcement: The ancient book was laid flat on an acid-free workbench. Nanocellulose UV adhesive was evenly sprayed onto the flocculated area using a sprayer, with a single spray volume controlled at 0.1 ml/cm².

Precise Curing: The UV LED light source was adjusted to a distance of 10 cm from the paper. A "scanning curing" mode (moving speed 5 mm/s) was used to complete local reinforcement within 1 second. After curing, excess adhesive was immediately absorbed with acid-free absorbent paper.

Performance Testing: The fiber strength of the reinforced paper increased to 85% of that of the original paper. After aging resistance testing (simulating 50 years of natural environment), there was no embrittlement or discoloration, and the adhesive layer did not cause ink bleeding in the ancient book.

Cultural relic restoration, a niche application of UV LEDs, has proven the technology's "flexible adaptability" through its successful implementation. By precisely controlling wavelength, steplessly adjusting power, and collaboratively developing materials, UV LEDs can overcome the limitations of traditional processes and achieve innovative applications in specialized fields with extremely high requirements for precision and safety. As the director of the Institute of Cultural Relics Protection stated, "This 'cold light' not only repairs the physical damage to cultural relics but also provides a new technological path for the inheritance of traditional cultural heritage."