company news about Application of UV LED technology in adhesive curing in the restoration of ancient architectural wood carvings

Application of UV LED technology in adhesive curing in the restoration of ancient architectural wood carvings

  In the field of ancient architectural preservation, wood carvings, due to their unique artistic value and historical significance, have always been a key and challenging aspect of restoration work. While repairing the wood carvings of an ancient building, a cultural relic preservation organization faced structural damage to the wood due to aging and insect infestation, necessitating the use of adhesives for reinforcement and repair. Traditional thermal curing methods suffer from drawbacks such as low efficiency, thermal damage to the delicate wood carvings, and unstable performance of the repair materials. Therefore, the organization introduced UV LED technology for adhesive curing, aiming to improve restoration efficiency, protect the cultural relics, and ensure quality.

  A UV LED light source with a wavelength of 365nm was selected, effectively stimulating the photoinitiator in the light-curing adhesive and ensuring a smooth curing reaction. The light source power was set at 500mW/cm² to ensure sufficient energy density and rapid curing of the adhesive. The UV LED light source was integrated into a portable restoration tool, making it easy to operate in the narrow or complex spaces often found in wood carving restoration. The operating distance between the light source and the repair area was strictly controlled at 2-3cm to avoid over-curing due to close proximity or under-curing due to distance. A specialized light-curing epoxy resin adhesive was used, characterized by its high strength, aging resistance, and low shrinkage, making it ideally suited to the needs of wood carving restoration. This adhesive has an A:B ratio of 2:1 and can be used directly at room temperature after mixing, effectively avoiding the air bubbles that can occur during traditional heat curing. The optimal curing parameters were determined through multiple experiments: an irradiation time of 30 seconds and a power of 500mW/cm². This parameter setting ensures simultaneous curing of both the surface and deeper layers of the adhesive, avoiding delamination or uncured areas and ensuring a high-quality cure.

  The project was implemented according to a strict process, covering material preparation, UV LED curing, curing test results, and post-repair protective treatment.
- Material Preparation: First, the damaged wood carving surface was cleaned and sanded to remove impurities and damage to ensure even adhesion of the adhesive. Subsequently, a light-curing epoxy adhesive was used to fill cracks and missing areas in the wood carving, preparing for subsequent curing.
- UV LED Curing: During curing, the UV LED light source was aimed at the repaired area at a distance of 2-3 cm and irradiated for 30 seconds. During this process, attention was paid to ensuring uniform light coverage to avoid uncured areas caused by shadows.
- Curing Test: The tensile strength of the cured adhesive was tested using a tensile tester to ensure it met the repair requirements (≥30 MPa). A hardness tester was also used to test the adhesive's hardness to ensure bond strength with the wood.
- Post-repair Protective Treatment: The repaired area was painted or stained to match the color and texture of the original wood carving, ensuring a harmonious appearance. In addition, the repaired area is treated with a UV protectant to prevent long-term exposure to UV rays that could cause material aging and extend the durability of the repair effect.

 The application of UV LED technology has achieved remarkable results, meeting expectations in terms of restoration efficiency, material protection, adhesive performance, and restoration results. Compared with traditional thermal curing methods, UV LED curing time is reduced by 70%, significantly improving restoration efficiency. This enables restorers to complete the work faster while minimizing disturbance to the wood carving surface during the restoration process. As a cold light source, UV LED causes virtually no thermal damage to the wood carving surface during the restoration process. The cured adhesive firmly bonds to the wood, avoiding the deformation or cracking that can occur with traditional thermal curing.The cured adhesive exhibits excellent performance, reaching a tensile strength of 35 MPa and a hardness of Shore D60, far exceeding the pre-set restoration requirements. Its low shrinkage also ensures the smoothness and aesthetics of the repaired area. The restored wood carving is virtually indistinguishable from the original, with a perfect blend of color and texture. Simulated environmental aging tests (such as high temperature, high humidity, and UV exposure) show that the adhesive performance in the repaired area remains stable, with no cracking or peeling, verifying the reliability of the restoration.

  By introducing UV LED technology, the cultural relics protection agency successfully addressed the challenges of inefficient and damaged woodcarving restoration on ancient buildings. UV LED technology not only significantly improved restoration efficiency but also significantly enhanced the quality of the restoration, resulting in a durable and aesthetically pleasing restoration that fully meets the requirements of cultural relics protection.