| 摘要 |
PURPOSE:To prepare pressure sensitive copying paper with controlled coloring fog, etc., by setting a layer containing synthetic polymer microcapsules having a specified average particle size and membrane thickness in which a specified phthalide derivative is sealed on a substrate. CONSTITUTION:A specified amount of a color coupler of a phthalide derivative represented by the formula I (R1: halogen atoms, C1-C4 alkyl groups, C1-C4 alkoxy groups, nitro groups, amino groups, etc.; R2: hydrogen atom, C1-C4 alkyl groups; R3-R6: hydrogen atom, C1-C6 alkyl groups, etc.; X, Y: hydrogen atom, C1-C4 alkyl groups; n: integer 0-4), a protecting agent, a water soluble binder, etc., are mixed to prepare a microcapsule coating solution. A substrate is coated with the microcapsule coating solution and dried to form a layer containing the microcapsules having an average particle size of 3-10mum and an average membrane thickness of 0.1-0.6mum. On the other surface of the substrate is formed a layer containing zinc salt of a salicylic acid derivative (an electron accepting developer) to obtain pressure sensitive copying middle paper. |
