Method for producing encapsulated structure and epoxy resin composition
A method for producing an encapsulated structure, the method including: a step of supplying granules or powder ( 1 ) formed from an epoxy resin composition to an extruder equipped with a screw ( 42 ) and a die ( 5 ) provided at the tip of the screw ( 42 ), and heating and melting the granules or powder ( 1 ) formed from the epoxy resin composition; a step of extruding the molten epoxy resin composition through the die ( 5 ) having a predetermined opening shape by rotation of the screw ( 42 ); a step of cutting the extruded epoxy resin composition ( 6 ) into a predetermined length to obtain a tablet formed from the epoxy resin composition, where the tablet has dimensions with a diameter of equal to or more than 40 mm and equal to or less than 100 mm and a length of equal to or more than 50 mm and equal to or less than 300 mm; a step of transferring the tablet to a transfer molding machine having a molding mold ( 30 ) in which an object to be encapsulated is disposed; and a step of obtaining an encapsulated structure by encapsulating the object to be encapsulated ( 11, 12 ) in the molding mold with the epoxy resin composition by a transfer molding method of using the transfer molding machine, in which the epoxy resin composition includes: an epoxy resin, a curing agent, an inorganic filler, a curing accelerator, and a wax having a melting point of equal to or higher than 30° C. and equal to or lower than 90° C.
1 . A method for producing an encapsulated structure, the method comprising:
a step of supplying granules or powder formed from an epoxy resin composition to an extruder equipped with a screw and a die provided at a tip of the screw, and heating and melting the granules or powder formed from the epoxy resin composition;
a step of extruding the molten epoxy resin composition through the die having a predetermined opening shape with a diameter of equal to or more than 40 mm and equal to or less than 100 mm by rotation of the screw at a temperature of equal to or higher than 80° C. and equal to or lower than 100° C., and wherein the die has a temperature of equal to or higher than 80° C. and equal to or lower than 100° C.;
a step of cutting the extruded epoxy resin composition using a cutter into a predetermined length to obtain a tablet formed from the epoxy resin composition, where the tablet has dimensions with a diameter of equal to or more than 40 mm and equal to or less than 100 mm and a length of equal to or more than 50 mm and equal to or less than 300 mm;
a step of transferring the tablet to a transfer molding machine having a molding mold in which an object to be encapsulated is disposed; and
a step of obtaining an encapsulated structure by encapsulating the object to be encapsulated in the molding mold with the epoxy resin composition by a transfer molding method of using the transfer molding machine,
wherein the epoxy resin composition includes:
an epoxy resin;
a curing agent;
an inorganic filler;
a curing accelerator; and
a wax having a melting point of equal to or higher than 30° C. and equal to or lower than 90° C.
2 . The method for producing an encapsulated structure according to claim 1 ,
wherein the step of encapsulating is carried out at a temperature of equal to or higher than 120° C. and equal to or lower than 200° C. and a pressure of equal to or higher than 3 MPa and equal to or lower than 15 MPa.