| 摘要 |
<p>PURPOSE: To provide a keyboard pad provided with all desirable properties including excellent elasticity and an excellent bending life by using the blend of the terpolymer (EPDM) of ethylene propylen dien monomer and the copolymer of propylene oxide and allyl glycidyl ether. CONSTITUTION: When parelan copolymer is added to the EPDM, the elasticity of this pad is practically improved without adversely affecting the bending life of the pad. It is appropriate to turn the ratio of the EPDM and the parelan coplymer to 10:90 or 90:10, it is desirable that the materials are present at the ratio of 40:60 or 60:40 and a best result 15 obtained when the two materials are at the ratio of almost 50:50. For the molding of the pad, the two kinds of rubber materials, that are the EPDM and the parelan copolymer, are mechanically mixed and homogenized. After blending them, an accelerator and other components are successively added. Thus, the optimum keyboard pad provided with the excellent bending life with the excellent elasticity is obtained.</p> |
