| 摘要 |
PURPOSE:To improve the productivity and the quality of the product by composing the title element of a compd. having at least 2 unsaturated cycloacetal groups per molecule, a compd. having 2 mercapto groups per molecule and a methacrylate compd. CONSTITUTION:The magnetic head element is sealed with the cross-linking product of a mixture consisting of a compd. having at least 2 unsaturated cycloacetal groups per molecule, a compd. having at least 2 mercapto groups per molecule and a filler or of the compds. and filler and a methacrylate compd. Although the mixing ratio of the acetal compd. to the mercapto compd. is not specially restricted, 0.25-1.5 equivalents of the mercapto compd. is preferably mixed with 1 equivalent of the acetal compd. in consideration of development of rancidity and the physical properties. Besides, the sum of the number of the unsaturated cycloacetal groups and the number of the mercapto groups is most preferably regulated to at least 5. Consequently, the productivity and resistance to heat and moisture are improved and the yield of magnetic head elements is also increased.
|
