JIS K5101-13-2-2004 "Pigment Test Methods, Part 13: Oil Absorption. Section 2 Boiling Flaxseed Oil Method", specifies the method for determining the oil absorption of pigments using boiling flaxseed oil. The standard specifies the sample weighing requirements, specifies the operation process of adding boiling flaxseed oil dropwise to the pigment until a specific state is formed, and details the calculation method of oil absorption, providing a unified technical standard for accurately assessing the absorption capacity of pigment to boiling flaxseed oil and measuring pigment performance.