Abstract:
Process provides wetlaid printed wiring board core stock precursor material that incorporates resin within cellulose matrix and that can be partially cured by conventional means to form PWB B-stage materials (20). Process also provides for reducing dielectric constant and dissipation factor of a PWB core stock and of PWB composite material made therefrom, by incorporating material having dielectric constant lower than that of cellulose fibers directly into cellulose matrix forming the core stock (21). Among materials that can be incorporated into cellulose matrix are fibrous materials, including glass fibers (23) and/or synthetic fibers, and/or particulate constituents such as glass microspheres, glass beads, glass shot, aramid fibers, aramid powders, ceramic microspheres, and clay. Other additives, such as flame retardants, may also be incorporated into novel paperboard materials of the invention.
Abstract:
This invention relates to an apparatus and a process for uniformly laminating a conductor (18) to a substrate (15). The conductor can be a printed circuit; the substrate can be any dielectric. The apparatus comprises two platens (10, 11) containing cavities (12, 13). One of the cavities (13) contains a mold (14) which is the mirror image of a substrate surface. The other cavity (12) substantially contains the substrate (15). It can have two-dimensional or three-dimensional surfaces to which the printed circuit is laminated. The product results in a superior lamination of the printed circuit across the surface of the substrate.
Abstract:
PROBLEM TO BE SOLVED: To provide an inexpensive printed circuit board of which production process can be shortened. SOLUTION: The printed circuit board is made of a paper base impregnated with resin, wherein a conductive paint is used to print a circuit on a board substrate without a copper foil layer. The board substrate may use a paper phenol board material where a paper substrate is impregnated with phenol resin, and a resist layer is formed on the board material, and then a conductive paint is preferably used to print a circuit thereon. COPYRIGHT: (C)2009,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide an electronic apparatus provided with a printed wiring board which can prevent the generation of an out-gas from a substrate base of a printed board due to the heat when soldering and previously prevent a bulge generated in a copper foil or a substrate base, in the electronic apparatus provided with a printed wiring board composed of a paper base phenolic copper-clad laminate for mounting an electronic component. SOLUTION: A copper foil pattern 23 having a continuous crest part and a valley part which substantially cross an advance direction X of a printed board 20 during solder dipping is formed, and a non-copper foil pattern section 27 having no copper foil 22 is provided oppositely to the copper foil pattern 23. With this configuration, since apexes 23c on the crest parts can be earlier cooled, a temperature gradient is generated and the heat during solder dipping moves. Along with the heat movement, the out-gas is guided to the apexes 23c of the crest parts, and can be easily discharged from the pattern section 27 near the apexes 23c. COPYRIGHT: (C)2006,JPO&NCIPI
Abstract:
A boron nitride fiber paper having a very small fiber diameter and exhibiting excellent heat resistance, mechanical properties and heat conductivity. The fiber paper is composed of a fiber assembly which contains boron nitride fibers having a fiber diameter of not more than 1 µm in an amount of not less than 40 wt%.
Abstract:
Provided is a nanofiber sheet that sufficiently refined by fibrillation and has high crystallinity of cellulose fiber and can realize a fiber-reinforced composite material exhibiting high transparency, a high elastic modulus, a low coefficient of linear thermal expansion, and high heat resistance and being high in flatness and smoothness. This nanofiber sheet includes crystalline cellulose as the main component and a lignin in an amount of from 10 ppm to 10 wt%. When a fiber/resin composite material obtained by impregnating the nanofiber sheet with tricyclodecane dimethacrylate, subjecting the impregnated product to UV-curing at 20 J/cm 2 , and heating the cured product in vacuum at 160°C for two hours includes 60 wt% of the cured tricyclodecane dimethacrylate and 40 wt% of nanofiber, the following physical characteristics (i) to (iii) are satisfied: (i) the parallel light transmittance of light of a wavelength of 600 nm at a sheet thickness of 100 µm is 70% or more; (ii) the Young's modulus is 5.0 GPa or more; and (iii) the coefficient of linear thermal expansion is 20 ppm/K or less.