| 摘要 |
PROBLEM TO BE SOLVED: To provide a dimethylsiloxane compound which is useful as an effective component of a hard coating agent, the hard coating agent capable of forming a hard coating film excellent in scratch resisting property, solvent resistance, and transparency on a substrate surface, and an optical disk in which warpage of the substrate caused by the formation of the hard coating film is suppressed. SOLUTION: This hard coating agent containing, as an effective component, a dimethylsiloxane compound shown by general formula (a) is applied, diluted if necessary, on a substrate, and the dimethylsiloxane compound is polymerized by heating or by irradiating an ultraviolet ray, and this hard coating film showing excellent scratch resisting property even if it is thin in thickness is formed on a substrate surface, for example, on a substrate of this optical disk. In the formula (a), m is a number of 1-10, n is a number of 6-36, R is shown by (CH2= CHCOOCH2)3CCH2- or (CH2=CHCOOCH2)3CCH2OCH2C(CH2-)(CH2OCOCH= CH2)2, and R' is a group selected from the groups of formulas (I)-(VI) shown in the specification. |
