使用油乳剂作触杀药剂已有多年的历史,乳剂的油料有植物油、石油、煤焦油等。我国以前曾大量地使用过植物油乳剂,但亦仅限於用在防治棉花蚜虫上,在防治果树害虫上则用者绝少。解放以前农村在长期剥削制度之下,农产品滞销,植物油在农村中多有剩馀,因此有使用植物油的条件。石油和煤焦油在旧中国工业不发达清况下,完全依赖国外的进口, The use of oil emulsion as contact agent has many years of history, the emulsion of vegetable oil, oil, coal tar and so on. China has previously used a lot of vegetable oil emulsions, but it is also limited to cotton aphids used in the prevention and control of fruit pests on the few users. Before the liberation of rural areas Under the long-term system of exploitation, due to the poor sales of agricultural products and the surplus of vegetable oil in the rural areas, the conditions for the use of vegetable oil were found. Under the undeveloped industrial conditions in old China, oil and coal tar completely relied on foreign imports,