Lacquer timber surface gives heavy blackening: The likelihood is knag going up Qi Qian was not sealed, classics sun is basked in, knag be heated, colophony from knag inside oozy and cause.

漆料表面出沉暗斑：可能是在上漆前未封住，经太阳一晒，受热，树从内渗出而引起的。