A method for producing a prepreg, includes the steps of (1) an opening step of opening glass fiber bundles to form plural glass fiber filaments, and (2) a step of aligning the plural glass fiber filaments formed in the previous opening step, on a thermosetting resin composition-coated surface of a carrier material so as to make the filaments run nearly parallel to each other in one direction thereon to form a prepreg. A method for producing a laminate, includes a step of preparing two or more prepregs formed in the previous step (2), laminating them in such a manner that, in at least one pair of prepregs, the running direction of the plural glass fiber filaments in one prepreg differs from the running direction of the plural glass fiber filaments in the other prepreg, and heating and pressing them.

The present disclosure relates to an integrally formed product including a metal and a fiber of biological origin disposed in dispersed state in the metal. A proportion by mass of the fiber of biological origin contained in the integrally formed product is within a range of 0.02 mass % or more and 10 mass % or less.

Devices and methods are described for reducing etching due to galvanic effect within a printed circuit board that may be used, for example, in a data storage device, such as a card-type data storage device. Specifically, a contact trace is coupled to a contact finger that has a substantially larger surface area than the contact trance, and that is configured to couple the data storage device to a host device. The contact trace is electrically isolated from the rest of the circuitry during a fabrication process. The contact finger and an exposed portion of the contact trace are plated with a common material to reduce galvanic etching of the contact trace during fabrication. The contact trace is then connected to an impedance trace though at least one of a component and a bond wire.

Provided is a prepreg capable of attaining thermal expansion coefficient reduction and elastic modulus increase without increasing the filling ratio of an inorganic filler therein and/or without using a resin having a low thermal expansion coefficient, and thereby capable of reducing warpage thereof. Specifically, provided is a prepreg containing glass fibers and a thermosetting resin composition, and containing a layer of plural glass fiber filaments aligned to run nearly parallel to each other in one direction. Also provided are a production method for the prepreg, a laminate containing the prepreg and its production method, a printed circuit board containing the laminate, and a semiconductor package having a semiconductor device mounted on the printed circuit board.

A thick conductor built-in type printed wiring board includes a printed wiring board, an insulating resin layer, an insulating base material layer, and a conductor layer. The printed wiring board includes an insulating layer including a cured product of a first resin composition, and a circuit provided on one main surface or both main surfaces of the insulating layer, the circuit having a plurality of conductor wirings each having a thickness ranging from 105 m to 630 m, inclusive. The insulating resin layer covers a surface of the printed wiring board on which the circuit is provided, and includes a cured product of a second resin composition and includes no fibrous base material. The insulating base material layer covers the insulating resin layer, and includes a cured product of a third resin composition and a fibrous base material. The conductor layer covers the insulating base material layer. The thick conductor built-in type printed wiring board does not include a void having a diameter of more than or equal to 10 m inside the thick conductor built-in type printed wiring board.

A circuit board includes at least one prepreg including a fiber layer, the fiber layer being woven with a plurality of first fibers arranged in a first direction and a plurality of second fibers arranged in a second direction that is substantially perpendicular to the first direction, and a circuit layer on at least one of opposite surfaces of the at least one prepreg. The at least one prepreg has a length in the first direction greater than a length in the second direction, each of the plurality of first fibers is formed of or includes a filling yarn, and each of the plurality of second fibers is formed of or includes a warp yarn.

A circuit board includes at least one prepreg including a fiber layer, the fiber layer being woven with a plurality of first fibers arranged in a first direction and a plurality of second fibers arranged in a second direction that is substantially perpendicular to the first direction, and a circuit layer on at least one of opposite surfaces of the at least one prepreg. The at least one prepreg has a length in the first direction greater than a length in the second direction, each of the plurality of first fibers is formed of or includes a filling yarn, and each of the plurality of second fibers is formed of or includes a warp yarn.

A thick conductor built-in type printed wiring board includes a printed wiring board, an insulating resin layer, an insulating base material layer, and a conductor layer. The printed wiring board includes an insulating layer including a cured product of a first resin composition, and a circuit provided on one main surface or both main surfaces of the insulating layer, the circuit having a plurality of conductor wirings each having a thickness ranging from 105 m to 630 m, inclusive. The insulating resin layer covers a surface of the printed wiring board on which the circuit is provided, and includes a cured product of a second resin composition and includes no fibrous base material. The insulating base material layer covers the insulating resin layer, and includes a cured product of a third resin composition and a fibrous base material. The conductor layer covers the insulating base material layer. The thick conductor built-in type printed wiring board does not include a void having a diameter of more than or equal to 10 m inside the thick conductor built-in type printed wiring board.

The present disclosure relates to an integrally formed product including a metal and a fiber of biological origin disposed in dispersed state in the metal. A proportion by mass of the fiber of biological origin contained in the integrally formed product is within a range of 0.02 mass % or more and 10 mass % or less.

An electro-thermal system includes a sensor support layer for indirectly mounting positionally related sensor components to a circuit board layer that supports electronic components without heat from these electronic components impacting a positional relationship between the sensor components. The sensor support layer may be a fiber reinforced plastic having a low coefficient of thermal expansion (CTE). Thus, heat that reaches the sensor support layer will not cause expansion that significantly affects the nominal position between the sensor components. The sensor support layer is mounted to the circuit board layer via an adhesive having an intermediate CTE that is greater than the CTE of the sensor support layer but less than the CTE of the circuit board layer. Thus, the sensor components are indirectly mounted to the circuit board layer which is free to expand and contract due to heat variations without changing the positional relationship between the sensor components.