Abstract: A thermosetting epoxy resin composition having a low environmental load and a high flame retardancy includes a compound represented by the following formula 1 and a novolac compound represented by the following formula 2 as essential components:X--R.sub.1 --X Formula 1X being a functional group, capable of reacting with a functional group Y of the formula 2; and R.sub.1 being a crystalline functional group having a phenyl group, ##STR1## Y being a functional group capable of reacting with the functional group X in the compound of the formula 1; R.sub.2 being a functional group capable of reacting with the functional group X, a hydrocarbon having 1 to 3 carbon atoms, or hydrogen; and n is an integer of 0 to 20.

Abstract: A flame retardant resin composition comprises a silicone resin having specific structure and weight-average molecular weight and a non-silicone resin having aromatic-ring. The silicone resin has R.sub.2 SiO.sub.1.0 units and RSiO.sub.1.5 units. The weight-average molecular weight of the silicone resin is in the range of not less than 10,000 to not more than 270,000. R is hydrocarbon group.

Abstract: A joining member for joining parts or materials to form a joined structure is constituted by a composite material containing a heating assistant in a matrix material. For disintegrating the joined structure, it is placed in a heating zone, and a high frequency magnetic field or a high frequency electric field, or a high frequency magnetic field and a high frequency electric field are applied to the joining member. The heating assistant may be in a form of a particle or a fiber containing at least one of a soft magnetic material, an electrically conducting material and a dielectric material. The matrix material may be plastic or ceramic. The disintegration of the joined structure can be efficiently and selectively carried out, thus contributing to efficient recycling.

Abstract: A joining member for joining parts or materials to form a joined structure is constituted by a composite material containing a heating assistant in a matrix material. For disintegrating the joined structure, it is placed in a heating zone, and a high frequency magnetic field or a high frequency electric field, or a high frequency magnetic field and a high frequency electric field are applied to the joining member. The heating assistant may be in a form of a particle or a fiber containing at least one of a soft magnetic material, an electrically conducting material and a dielectric material. The matrix material may be plastic or ceramic. The disintegration of the joined structure can be efficiently and selectively carried out, thus contributing to efficient recycling.

Abstract: The method of recovering valuables from a printed wiring board on which electronic components are mounted, includes the steps of (a) removing electronic components from a printed wiring board on which the electronic components are mounted, (b) polishing a surface of the printed wiring board from which the electronic components have been removed in the step (a), (c) milling the printed wiring board a surface of which has been polished in the step (b), and (d) separating milled portions of the printed wiring board into portions mainly including copper and portions mainly including resin and filler. The electronic components recovered in accordance with the method includes valuables such as gold having greater grade than natural minerals. The copper recovered in accordance with the method includes no impurities such as solder, and thus can be reclaimed as metal resource having high added value.

Abstract: A printed wiring board, on which an electronic parts are mounted and fixed by way soldering, is introduced into a heating furnace for heating at a temperature higher than or equal to a melting temperature of a solder. After sufficiently melting of solder, an impact force and/or a shearing force are applied. By this under a reduced connecting force, the electronic parts are removed from a printed wiring board. On the other hand, since the parts can be easily removed from the printed wiring board. Also, the parts and the printed circuit are separated for collecting useful substance and can improve resistance to enhance recycling efficiency.

Abstract: In a method of grinding a printed circuit board, a printed circuit board having various parts mounted thereon, or a residual ground product produced in the manufacturing process for the boards, and recovering valuable substances by separating the ground product into a portion containing a large amount of metal component such as copper and a portion consisting a resin, a filler material, and the like through a separation step, the separation step includes a specific gravity separation step of separating the ground product into a portion containing a large amount of substance having a high specific gravity and a portion containing a large amount of substance having a low specific gravity, and an electrostatic separation step of separating the ground product into a portion having a large amount of conductor and a portion containing large amount of insulator. The grinding step includes a coarse grinding step and a fine grinding step.

Abstract: An epoxy resin composition is provided for encapsulating a semiconductor. The resin composition contains an epoxy resin, a phenol resin, a phenol-modified silicon-containing compound and an inorganic filler. The phenol-modified silicon-containing compound is obtained by reacting a first and/or second organic silicone compound (formulae (1-a), (1-b) and (2)) with an organic silicon compound (formula (3)) and with a phenol resin: ##STR1## wherein X stands for an organic group containing an epoxy group, Y for a polyoxyalkylene group and Z for a mercapto group, an amino group or a ureido group.