The invention relates to a synthetic method of a 2,2-diethoxy
acetophenone photoinitiator, which comprises the following steps: a, synthesizing
ethyl nitrite, namely mixing
ethanol with 28 percent of
aqueous solution of
sodium nitrite in a reaction kettle with mechanical stirring and a gas ingress
pipe, dripping 20 percent dilute sulphuric acid into the mixture at the temperature of between 20 and 30 DEG C to generate
ethyl nitrite gas, and directing introducing the generate
ethyl nitrite gas into the step b for reaction, wherein the
molar ratio of the
ethanol to the
sodium nitrite to the dilute sulphuric acid is 1.00:1.09 to 1.68:1.10 to 1.18; and b, synthesizing 2,2-diethoxy
acetophenone, namely introducing the ethyl
nitrite gas generated by the step a into
acetophenone and 36 percent
hydrogen chloride ethanol solution, and neutralizing the mixture by using
sodium hydroxide solution after a reaction ends to prepare finished products, wherein the
molar ratio of the acetophenone to the
hydrogen chloride ethanol solution is 1:1. The synthetic method is simple and convenient in process and high in product yield and is suitable for industrial production.