| 摘要 |
<p>PURPOSE:To obtain laminate free from flashes, excellent in mold releasing property and accurate in thickness by molding the prepreg obtained by impregnating the peripheral edge of a sheet base material with water and then thermosetting resin varnish. CONSTITUTION:Part or all of the peripheral edge of a sheet base material is impregnated previously with water or organic solvent containing water of 50% or more, then this base material is impregnated with thermosetting resin varnish to obtain prepreg. Then, several sheets of this prepreg are heaped up, heated, compressed and molded to prepare laminates. Paper such as kraft paper, linear paper, glass unwoven fabric, glass-paper mixed unwoven fabric, glass cloth, cotton cloth, etc. are used as the base material. Water-soluble solvent such as alcohol group like methanol etc., ketone group like acetone etc. is suitable to organic solvent. As the treating method, the base material is preferred to be impregnated previously with water or organic solvent containing water 5% min. by means of the spray method or the dropping impregnation method.</p> |
