◆ Engine oil is the largest type of lubricating oil products. With the development of our country's economy, the use of automobiles in our country will be popularized with a faster speed, so engine oil will become the lubricating oil products that are closely related to ordinary users. The quality of oil directly affects the user's confidence in the oil used. But for the average user. In the case of not understanding the performance of the oil, only judging the quality of the oil by subjective feelings, often lead to misjudgment, and often cause users to misunderstand the lubricant production enterprises; On the other hand, it also causes unnecessary losses to users.

◆ According to the color of the oil to determine the quality of the oil is a simple method usually used by engine oil users. The change of oil color can sometimes reflect the quality of the oil. But oil color change is not the only basis for determining oil quality.

◆ The initial color of the engine oil depends on the color of the base oil and additives, and the color of the general base oil will not be much different. Therefore, the initial color of the oil is mainly determined by the depth of the additive color. The additive color produced by different manufacturers of the same grade of oil is different. Generally does not indicate the quality of the oil. Therefore, the problem of oil blackening should have a correct understanding. According to the oil researchers using the method of tracer atoms, it is determined that about 70% of the blackening of oil is caused by external factors, and the other is caused by the base oil of the oil itself, additives and other factors.

◆ Oil color change can be analyzed from two aspects; The influence of internal and external factors during the use of oil - the color change of the oil itself during the use of oil