Abstract:
The problem to be solved by the invention is to provide an epoxy resin composition for a prepreg, which is used in the manufacture of a printed circuit board containing a multilayer printed circuit board, wherein the epoxy resin composition for a prepreg is characterized by containing as essential components, a phosphorus compound that has 1.8 or more and less than 3 on average of a phenolic hydroxyl group that is reactive to an epoxy resin in the molecule, and that has 0.8 or more on average of a phosphorus element; a bifunctional epoxy resin that has 1.8 or more and less than 2.6 on average of epoxy groups in the molecule; a multi-functional epoxy resin that contains 2.8 or more on average of epoxy groups in one molecule; a hardening agent; an inorganic filler; and a molybdenum compound, wherein the epoxy resin composition for a prepreg is obtained by blending a pre-reacted epoxy resin, which is obtained by reacting at least the phosphorus compound with the bifunctional epoxy resin and the multi-functional epoxy resin, or the bifunctional epoxy resin only in advance, the bifunctional epoxy resin or the multi-functional epoxy resin, the hardening agent, the inorganic filler, and the molybdenum compound, which is excellent in flame retardance, heat resistance, thermal stiffness, and excellent in hole position accuracy without the production of a harmful substance at the time of combustion, a prepreg using the epoxy resin composition for a prepreg, and a multilayer printed circuit board using the prepreg.
Abstract:
Provided is a circuit board including a resin base, and a resistance element formed above the resin base. The resistance element includes a resistance pattern including an electrode portion and an extending portion, and an electrode formed on the electrode portion of the resistance pattern and including a foot portion reduced in thickness toward the extending portion.
Abstract:
A urinal includes: a urinal body; a high-frequency sensor which radiates a radio beam obliquely passing through an upper surface of the urinal body toward a bowl and receives a reflected wave from an object so as to generate a detection signal; and a valve which discharges or stops flushing water to the urinal body in response to the detection signal. An angle formed between a first plane including the upper surface of the urinal body and a second plane including a radiation surface of an antenna of the high-frequency sensor is in a range of more than 0 degree to less than 90 degree. A cross line where the first plane and the second plane intersect with each other is substantially parallel to a horizontal direction of the urinal body. The radio beam is a linearly-polarized wave. An excitation direction of the radio beam intersects with the cross line. An intensity of the radio beam passing through the urinal body is larger than that of the radio beam reflected by the upper surface.
Abstract:
The core layer of a core substrate is made of carbon fibers impregnated with resin. When the temperature of the core layer increases, the core layer suffers from an increase in the thickness because of thermal expansion of the resin. The core layer is sandwiched between the insulating layers containing glass fibers. The insulating layers serve to suppress an increase in the thickness of the core layer resulting from the thermal expansion of the core layer. Thermal stress is suppressed in the core substrate.
Abstract:
Large-sized through holes are formed in a core layer of a printed wiring board. Large-sized vias are formed in the shape of a cylinder along the inward wall surfaces of the large-sized through holes located within a specific area. A filling material fills the inner space of the large-sized via. A small-sized through hole penetrates through the corresponding filling material along the longitudinal axis of the small-sized through hole. A small-sized via is formed in the shape of a cylinder along the inward wall surface of the small-sized through hole. The filling material and the core layer are uniformly distributed within the specific area in the in-plane direction of the core substrate. This results in suppression of uneven distribution of thermal stress in the core layer in the in-plane direction of the core layer.
Abstract:
A semiconductor device includes a support body, a first substrate provided on a surface at one side of the support body, a second substrate provided on a surface at the other side of the support body, and a semiconductor chip provided on the first substrate exposed to an opening part piercing the support body and the second substrate. The first substrate includes a first dielectric layer and a wiring layer, a plurality of first electrodes connected to the semiconductor chip which first electrodes are provided on a first surface of the first substrate exposed to an inside of the opening part, and the second substrate includes a second dielectric layer made of a material substantially the same as the first dielectric layer.
Abstract:
A method for recycling in place an asphalt mixture layer of a paved road continuously, while moving a self-propelled vehicle system, which comprises a step of heating and softening the asphalt mixture layer, a step of scraping and breaking said hot and softened asphalt mixture layer and keeping the softened mixture at a temperature sufficient not to form an aggregate, to prepare an asphalt mixture having a single-grained structure, a sieving step of classifying said asphalt mixture having a single-grained structure into a plurality of grain size groups, a step of designing mix proportions for converting said asphalt mixture to a recycled asphalt mixture by the use of said plurality of grain size groups classified, a step of mixing uniformly said recycled asphalt mixtures having designed mix proportions, and a step of spreading and compacting said recycled asphalt mixtures having been mixed uniformly, to thereby form a recycled asphalt mixtures layer.
Abstract:
A semiconductor device includes a support body, a first substrate provided on a surface at one side of the support body, a second substrate provided on a surface at the other side of the support body, and a semiconductor chip provided on the first substrate exposed to an opening part piercing the support body and the second substrate. The first substrate includes a first dielectric layer and a wiring layer, a plurality of first electrodes connected to the semiconductor chip which first electrodes are provided on a first surface of the first substrate exposed to an inside of the opening part, and the second substrate includes a second dielectric layer made of a material substantially the same as the first dielectric layer.
Abstract:
The wiring board comprises a plate-shaped conductive core material 10 with a through-hole 12 formed in, an insulation layer 14 formed on the surface of the conductive core material 10 and on the inside wall of the through-hole 12, a resin 18 buried in the through-hole 12 with the insulation layer 14 formed in, wirings 22a, 22b formed on the upper surface and the undersurface of the conductive core material 10 with the insulation layer 14 formed on, and an wiring 22d formed in the through-hole 20 formed in the resin 18 and electrically connected to the wirings 22a, 22b.
Abstract:
A printed wiring board is made of first and second substrates superimposed on each other. The first and second substrates respectively include a core layer made of resin containing carbon fibers. The second substrate has the outline different from that of the first substrate. A stepped surface is defined on the front surface at least of the first substrate. Electrodes can be formed on the stepped surface as well as on the back surface of the first substrate and the front surface of the second substrate. This structure enables detection of an electric signal from the stepped surface. A further flexibility can thus be achieved in locating electrodes as compared with a conventional printed wiring board having uniform substrates simply superimposed on each other. This results in an expanded use or purpose for a printed wiring board.