A novel strategy has been developed to achieve multi-color ultralong room-temperature phosphorescence (RTP) using carbonized polymer dots (CPDs). The approach involves using o-phenylenediamine as a precursor to generate multiple luminescent centers and polyacrylic acid to synthesize CPDs. These CPDs are then embedded in a rigid B₂O₃ matrix, which synergistically limits nonradiative losses through polymer cross-linking and the rigid matrix. The resulting CPD-based materials exhibit remarkable ultralong phosphorescence in blue and lime green, with a visible lifetime of up to 49 seconds and high phosphorescence quantum yield. The phosphorescence mechanism is attributed to the introduction of multiple luminescent centers and the cross-linking-enhanced emission (CEE) effect, which reduces nonradiative loss of triplet excitons. The oP-CDs@B₂O₃ material demonstrates dual-color phosphorescence, long phosphorescence lifetime, and high quantum yield, making it suitable for applications in anti-counterfeiting and information encryption. The material was tested for practical applications, including the creation of anti-counterfeiting patterns and QR codes, which showed stable phosphorescence even after six months of storage at room temperature. The study highlights the potential of CPD-based RTP materials in various applications due to their unique properties, including long phosphorescence lifetime, high quantum yield, and dual-color emission. The results demonstrate the effectiveness of the synergistic enhancement structure design in achieving ultralong phosphorescence and enhancing the practical applicability of RTP materials.A novel strategy has been developed to achieve multi-color ultralong room-temperature phosphorescence (RTP) using carbonized polymer dots (CPDs). The approach involves using o-phenylenediamine as a precursor to generate multiple luminescent centers and polyacrylic acid to synthesize CPDs. These CPDs are then embedded in a rigid B₂O₃ matrix, which synergistically limits nonradiative losses through polymer cross-linking and the rigid matrix. The resulting CPD-based materials exhibit remarkable ultralong phosphorescence in blue and lime green, with a visible lifetime of up to 49 seconds and high phosphorescence quantum yield. The phosphorescence mechanism is attributed to the introduction of multiple luminescent centers and the cross-linking-enhanced emission (CEE) effect, which reduces nonradiative loss of triplet excitons. The oP-CDs@B₂O₃ material demonstrates dual-color phosphorescence, long phosphorescence lifetime, and high quantum yield, making it suitable for applications in anti-counterfeiting and information encryption. The material was tested for practical applications, including the creation of anti-counterfeiting patterns and QR codes, which showed stable phosphorescence even after six months of storage at room temperature. The study highlights the potential of CPD-based RTP materials in various applications due to their unique properties, including long phosphorescence lifetime, high quantum yield, and dual-color emission. The results demonstrate the effectiveness of the synergistic enhancement structure design in achieving ultralong phosphorescence and enhancing the practical applicability of RTP materials.