Abstract:
PROBLEM TO BE SOLVED: To provide a fluororesin substrate allowing sufficient suppression of warpage occurrence in reflowing and also exhibition of sufficiently excellent, high-frequency properties.SOLUTION: A fluororesin substrate is a fluororesin substrate where a dielectric layer with fluororesin being a main component is formed on a metal conductor and the dielectric layer contains hollow glass beads. The metal conductor has a surface roughness Rz (JIS B 0601-1994) of 2.0 μm or less. The fluororesin is irradiated with ionizing radiation in an irradiation dose of 0.01 to 500 kGy. The fluororesin is one, two, or more kinds of polytetrafluoroethylene (PTFE), a tetrafluoroethylene-perfluoroalkylvinyl ether copolymer (PFA), a tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and a tetrafluoroethylene-ethylene copolymer (ETFE).
Abstract:
A circuit subassembly is disclosed comprising a conductive metal layer and a dielectric substrate layer having a dielectric constant of less than about 3.5 and a dissipation factor of less than about 0.006 at 10 GHz, wherein the composition of the dielectric substrate layer comprises about 5 to about 70 volume percent of borosilicate microspheres that have been treated with an alkaline solution.
Abstract:
A circuit board may include a substrate, an interconnected structure associated with the substrate, and a solder mask associated with the interconnected structure and the substrate. The solder mask may be based on a mixture that includes epoxy and a powder. The powder may be hollow glass micro-balloons.
Abstract:
The present invention herein provides fine inorganic hollow powder having a high hollowness rate, which can be incorporated into, for instance, a low dielectric rubber or resin composition. The inorganic hollow powder has an average hollowness rate of higher than 70% by volume and an average particle size ranging from 3 to 20 μm and the powder preferably has an average hollowness rate ranging from 75 to 85% by volume, an average particle size ranging from 5 to 15 μm, a maximum particle size of not more than 25 μm, a specific surface area of not more than 10 m2/g, an average sphericity degree of not less than 0.90 and a purity of not less than 99% by mass. The inorganic hollow powder can be prepared by a method comprising the steps of forming a flame using a burner provided with at least a triplet-tubular portion comprising, in order from the outermost side, a combustion-improving gas-supply pipe, a combustible gas-supply pipe and an inorganic raw powder-supply pipe assembled together; injecting, into the flame at a high discharge speed, inorganic raw powder having a specific particle size through the inorganic raw powder-supply pipe, while the powder is entrained with a carrier gas having a specific relative humidity, to thus subject the powder to a heat-treatment.
Abstract:
Disclosed are liquid crystalline polymer compositions, which are melt moldable, and which contain a perfluorinated polymer, and a particulate aramid, and optionally contain hollow glass or quartz spheres, and which usually have low dielectric constants. They are particularly useful as electrical connectors and substrates for other electronic applications which use high frequency signals.
Abstract:
An electronic package (10) is provided which includes a circuit board (12) having a substrate (14) and circuitry (16) and a surface mount device (22) having a contact terminal (24). A mounting pad (28) is formed on the circuit board (12). The electronic package (10) also includes a solder joint (30) connecting the contact terminal (24) of the surface mount device (22) to the mounting pad (28) on the circuit board (12). The solder joint (30) includes a reflowable solder and a plurality of stand-off members (32 or 42). The stand-off members (32 or 42) provide a separation distance (H) between the circuit board (12) and surface mount device (22) in the range of about 0.01 mm to 0.10 mm.
Abstract:
Disclosed are liquid crystalline polymer compositions, which are melt moldable, and which contain a perfluorinated polymer, and a particulate aramid, and optionally contain hollow glass or quartz spheres, and which usually have low dielectric constants. They are particularly useful as electrical connectors and substrates for other electronic applications which use high frequency signals.
Abstract:
The present invention provides coated fiber strand comprising at least one fiber having a residue of an aqueous forming size composition applied to at least a portion of a surface of the at least one fiber, the aqueous forming size composition comprising: (a) at least one starch; (b) at least one film-forming material; (c) at least one lubricant; and (d) a plurality of discrete particles that provide interstitial space between the at least one fiber and at least one adjacent fiber sufficient to allow wet out of the fiber strand. In one embodiment of the invention, the fibers are glass fibers, the at least one starch comprises an oleophobic starch, the at least one film-forming material comprises a N-vinyl amide polymer, the at least one lubricant comprises an ester, and the particles are dimensionally stable particles selected from polymeric organic materials, non-polymeric organic materials, polymeric inorganic materials, non-polymeric inorganic materials, composite materials and mixtures thereof. In one non-limiting embodiment of the invention, the particles comprise hexagonal boron nitride particles and/or hollow particles formed from a copolymer of styrene and acrylic monomer. The present invention also provides a fabric incoporating the coated fabric strand and an electronic support and an electronic circuit board incorporating the fabric.