| 摘要 |
PURPOSE:To enhance the durability of recording and erasure by suppressing the lowering of turbidity due to the repetition of printing-erasure by using a crosslinked resin in a reversible thermal recording medium and controlling the crosslinking density of a resin matrix and high temp. storage elastic modulus. CONSTITUTION:The crosslinking density rho of a resin matrix used in a reversible thermal recording medium is set to 3.50X10<-4>mol/cm<3> or more. Herein, rho is rho=E''/3phiRT [wherein E' is storage elastic modulus within a rubber region (Tg+40 deg.C) due to the measurement of dynamic viscoelasticity, phi is phi (front coefficient) 1, R is a gas constant and T is absolute temp.]. When the crosslinking density of the resin matrix is specified and the storage elastic modulus at high temp. (140 deg.C) is controlled, the lowering of turbidity due to the repetition of printing-erasure can be prevented and the durability of erasure can be enhanced to a large extent. |
