| 摘要 |
PURPOSE:To obtain the above mentioned product having a superior capacity, such as a good heat resisting property and low permeability, by polymerizing urea and HCHO under the existence of gum arabic and forming urea/HCHO resin wall around hydrophobic oily liquid. CONSTITUTION:Urea and HCHO are polymerized at the following cundition, that is, pH of whole system to be at less than 7, preferably less than 4, 5, temperature to be at 10-95 deg.C, most suitably 50-70 deg.C and mole ratio of HCHO against urea to be 0.6-5, most suitably 1.4-3. Then, urea/HCHO resin wall is formed around hydrophobic oily liquid by using the above solution. By the above method, capsule solution having a low viscosity and high concentration, is able to simply obtain and easy washable capsule having a least adhesion of resin on reaction vessel, is able to obtain at a low cost and also the above capsule is useful for microcapsule for pressure sensitive recording paper especially. |
