Can UHPC Shapes Achieve Gradient Color Effects? Coloring Processes and Color Control Technology

The color gradient effects of UHPC shapes can be achieved through various techniques such as integral coloring, surface coatings, and digital printing, with color transition naturalness of ΔE≤3.0 and weather resistance reaching Grade 7-8. In the light-transmitting UHPC project at Shanghai Century Plaza, Qinglong Group successfully achieved a smooth gradient from warm yellow to cool white through mineral pigment layered casting technology, with long-lasting and stable results. Color gradients not only enhance artistic expressiveness but also expand the application boundaries of UHPC in architecture.

Integral coloring is the most durable solution. Different colored slurries are added during mixing, and color blending is achieved by controlling the casting sequence and vibration process. Qinglong Group adopts a dual-pumping system to precisely control the proportions of each colored slurry and the blending zones, with adjustable gradient band width (10-50cm). Iron oxide-based inorganic pigments are selected for their strong light resistance and firm bonding with the matrix, offering a lifespan that matches that of UHPC.

Surface coatings are suitable for complex gradients. Using digital inkjet technology, patterns are printed directly on the exterior surface with a resolution of up to 1440dpi. A primer is first applied to enhance adhesion, and a protective coating is applied after printing. In a commercial complex project in Nanning, photo-quality image effects were achieved using UV-cured inks. Regular maintenance keeps the colors vibrant.

Color control requires precision throughout the entire process. Standard color cards are established, and color difference testing is conducted for each batch during mass production. The curing regime affects color uniformity, requiring strict control of temperature and humidity. Qinglong Group keeps color difference fluctuations within ΔE≤1.5 through an automated color matching system, ensuring consistent gradient effects. The color expressiveness of UHPC is opening a new chapter in architectural art.