Abstract: A displacement prevention coating agent is provided which can prevent a displacement in lens processing, which is soluble in water and which exhibits a transparent appearance at least after being cured. The displacement prevention coating agent may coat the front and rear surfaces of a lens so that when cutting processing is performed on an end surface of the lens, a holding position of the front and rear surfaces of the lens held by a chuck device is prevented from being displaced. A water-repellent coat layer may be formed as a membrane such that the end surface has a shape corresponding to a frame. The displacement prevention coating agent may be formed of an aqueous solution whose main components are a hydrophilic resin, a surfactant having a perfluoro group and an emulsion.

Abstract: [Problem to be Solved] A displacement prevention coating agent is provided which can prevent a displacement in lens processing, which is soluble in water and which exhibits a transparent appearance at least after being cured. [Solution] There is provided a displacement prevention coating agent with which the front and rear surfaces of a lens are coated so that when cutting processing is performed on an end surface of the lens where, for example, a water-repellent coat layer is formed as a membrane such that the end surface has a shape corresponding to a frame, a holding position of the front and rear surfaces of the lens held by a chuck device is prevented from being displaced, where the displacement prevention coating agent is formed of an aqueous solution whose main components are a hydrophilic resin, a surfactant having a perfluoro group and an emulsion and exhibits a transparent appearance at least after the formation of the membrane.

Abstract: A plastic lens of a multilayer film structure forms an organosiloxane-based hard coating film formed on a surface of a lens substrate as a first layer, an inorganic oxide-based antireflection film formed on the hard coating film as a second layer, and a water-repellent thin film obtained by polycondensing an organosilicon compound and formed on the antireflection film as a third layer, pencil hardness of the surface of the lens on which these plural layer films are formed being from 3H to 7H, and an initial falling angle of oleic acid on the surface of the lens on which these plural layer films are formed being 20° or less.

Abstract: A plastic lens of a multilayer film structure forms an organosiloxane-based hard coating film formed on a surface of a lens substrate as a first layer, an inorganic oxide-based antireflection film formed on the hard coating film as a second layer, and a water-repellent thin film obtained by polycondensing an organosilicon compound and formed on the antireflection film as a third layer, pencil hardness of the surface of the lens on which these plural layer films are formed being from 3H to 7H, and an initial falling angle of oleic acid on the surface of the lens on which these plural layer films are formed being 20° or less.