A coating liquid for an intermediate layer of an electrophotographic photoconductor comprises at least one of alcohol solvents; and N-methoxymethylated nylon, in which the N-methoxymethylated nylon has solution viscosity within a range from 43 mPa\xb7s to 50 mPa\xb7s when dissolving into methanol at 30\xb0 C. The average pressure difference method results in improved doser efficiency monitoring. The concavity and convexity engage to facilitate locking together of the head and handle. The invention also provides an eyewear assembly including primary eyeglasses, a detachable nose pad assembly, and an auxiliary eyeglass unit also provided with a nose pad assembly similar to the assembly.