Abstract:
Biobased cross-linked compositions, methods of fabrication and structures, in particular biobased printed wiring boards using the compositions and methods of making the structures are described. Biobased materials such as lignin, crop oils, wood resins, tannins, and polysaccharides and combinations thereof are cross-linked, preferably using heat, a cross-linking agent, and an initiator. The materials fabricated have suitable properties for printed wiring boards which are made by impregnating a fibreglass or biobased cloth with an admixture of the biobased material, cross-linking agent and initiator which is processed by conventional methods to produce a printed wiring board.
Abstract:
The present invention provides a lightweight prepreg having uniform formation, low linear thermal expansion coefficient and good mechanical strength, comprising a porous para-oriented aromatic polyamide film and a thermoplastic resin and/or a thermosetting resin, the porous para-oriented aromatic polyamide film being impregnated with the thermoplastic resin and/or the thermosetting resin, a process for producing the same, and a printed circuit substrate/board using the same. A process for producing for producing a prepreg comprising a porous para-oriented aromatic polyamide film and a thermoplastic resin and/or a thermosetting resin, the porous para-oriented aromatic polyamide film being impregnated with the thermoplastic resin and/or thermosetting resin, which comprises the following steps (a) to (d):
step (a) of forming a film-like material from a solution containing 1 to 10% by weight of a para-oriented aromatic polyamide having an inherent viscosity of 1.0 to 2.8 dl/g and 1 to 10% by weight of a chloride of an alkaline metal or an alkaline earth metal in a polar amide solvent or a polar urea solvent; step (b) of maintaining the film-like material at a temperature of not less than 20°C or not more than -5°C to deposit the para-oriented aromatic polyamide from the film-like material; step (c) of immersing the film-like material obtained in the step (b) in an aqueous solution or an alcoholic solution to elute the solvent and the chloride of the alkaline metal or alkaline earth metal, followed by drying to obtain a para-aramid porous film; and step (d) of impregnating the porous film obtained in the step (c) as a substrate with the thermoplastic resin and/or thermosetting resin to produce a prepreg.
Abstract:
A woven or nonwoven fabric made of a mixture of at least two of meta-aramid, polyethylene terephthalate and glass fibers is impregnated with a solution of an adduct of an epoxy resin and a copolymer of acrylonitrile and butadiene having carboxyl groups at both chaim ends; as a preliminary reaction product or mixed with another epoxy resin. A curing agent maybe included in the solution. The dried impregnated fabric is dried and a metal foil, e.g. of copper, is placed over at least one face of the fabric base and is laminated thereto by heat and pressure. The resultant laminate is usable as a printed circuit board and can be bent to a desired shape.
Abstract:
A composite containing high purity crystalline ceramic fibers in a polymeric matrix, suitable for use as a microelectronic device package or circuit board. The composite exhibits high thermal conductivity, and low coefficients of thermal expansion in-plane, and moderate thermal conductivities and low dielectric constants out-of-plane.
Abstract:
Laminated synthetic mica articles are disclosed that have particular applicability as substrates in electronic components. The articles comprise a core of stacked and consolidated, synthetic mica sheets that are impregnated with resin, and a copper foil sealed to a face on the article. Adherence of the copper foil is enhanced by use of a micaceous facing layer and bonding sheet, both being resin-impregnated and the resin cure being advanced beyond the normal B-stage level before assembly. Insulation resistance is enhanced by providing an advanced resin coating on the copper foil before assembly. Use of a bismaleimide triazine and epoxy mixed resin is also disclosed whereby a transformation temperature (Tg) of about 200°C. is obtained.
Abstract:
A flame-retarded copper-clad laminate is provided comprising a plurality of paper substrate layers each impregnated with an unsaturated polyester resin and a copper cladding adhesively bonded onto at least one side thereof. The improvement comprises said unsaturated polyester resin containing an aliphatic and/or alicyclic brominated flame-retardant and aromatic brominated flame-retardant in combination.
Abstract:
An electrical laminate comprising a plurality of fibrous cellulosic substrated layers (1) and alternately interposed layers of cured epoxy or unsaturated polyester resin (2) between the adjacent substrate layers, wherein each of the substrate layers is embedded in a matrix.of said cured resin which is substantially integral with said layers of cured resin, and consists essentially of cellulosic fibers having thereon a coating of methylol group-containing resin such as aminoplast resins. The laminate may be unclad or cladded with a metal foil.