abstract |
[Problems] White laminates for print wire boards heretofore have problems of discoloring of thermosetting resin portion and reduction of reflectance. In LEDs of type using UV emitting device have not been appropriate in mounting recent high luminous intensity LED, a requirement for substrates which are not discolored towards UV and heat is becoming strong, since substrates on which the LED chip is mounted are deteriorated and discolored by UV. Further, in mounting chip LED, accuracy of board thickness is also required in order to avoid liquid leakage during sealing process of the chip LED. n [Means for Solving the Problems] White prepreg according to the present invention is characterized in that it comprises a dried product of a resin composition (E) impregnated on a sheet glass fiber substrate; said composition (E) containing, as essential ingredients, an epoxy resin (A) comprising a cycloaliphatic epoxy resin (A1), a glycidyl (meth)acrylate polymer (B), a white pigment (C), and a curative (D). Besides, a white laminate of this invention is characterized in that it comprises a product obtainable by pressure molding under heating of one sheet or plural sheets of a white prepreg as above. |