METHOD FOR PRODUCING FILM FOR DIE CASTING MOLD, THE FILM, AND MOLD FOR DIE CASTING WITH THE FILM FORMED ON CAVITY FACE

To provide a mold for die casting having excellent seizure resistance to a molten metal and high durability without causing deterioration in the quality of a die-cast product.SOLUTION: A water-in-oil type (W/O type) emulsion using an aqueous solution of a metal salt and also using an alcohol solution of an organic siloxane precursor as a dispersoid is applied to a cavity face, and is dried/cured. Thus, a film, which consists of organic siloxane including the metal salt and has a Vickers hardness of 15 to 300 HV, in which a plurality of recessed parts with a diameter of 0.5 to 2 μm and a depth of 0.1 to 1 μm are formed on a surface of the film, and the ratio of an area of the recessed parts on the surface is 20 to 80%, is formed on the cavity face of a mold for die casting.SELECTED DRAWING: Figure 17 【課題】ダイカスト鋳造品の品質の低下を招くこと無く溶湯に対する優れた耐焼付き性及び高い耐久性を有するダイカスト用金型を提供する。【解決手段】金属塩の水溶液を分散質とし且つ有機シロキサン前駆体のアルコール溶液を分散媒とする油中水滴型（Ｗ／Ｏ型）エマルションをキャビティ面に塗布して乾燥・硬化させる。これにより、金属塩を含む有機シロキサンからなり、１５乃至３００ＨＶのビッカース硬度を有し、０．５乃至２μｍの直径及び０．１乃至１μｍの深さを有する複数の凹部が表面に形成されており、且つ当該被膜の表面に占める上記凹部の面積の割合が２０乃至８０％である被膜を、ダイカスト用金型のキャビティ面に形成する。【選択図】図１７