Abstract:
A heat-resistant synthetic fiber sheet which comprises 40 to 97 mass % of heat-resistant organic synthetic polymer short fibers and 3 to 60 mass % of a heat-resistant organic synthetic polymer fibrid and/or an organic resin binder for binding them, wherein at least a part of the short fibers has both end surfaces having an angle of inclination of 10 degree or more to the plane intersecting orthogonally to the fiber axis thereof. The heat-resistant synthetic fiber sheet is useful as a substrate for a laminate for an electric circuit board.
Abstract:
The present invention relates to a nonwoven substrate, and specifically to a nonwoven substrate imparted with a three-dimensional image, wherein the three-dimensional nonwoven substrate is particularly suited as a support substrate for a PCB (printed Circuit Board) and similar application. The nonwoven substrate is formed from a precursor web (P) which undergoes entangling treatment by entangling manifolds (16, 20, 24'). By the utilization of a hydroentangled, three-dimensionally imaged support substrate impregnated with a durable resinous matrix, PCB's, and similar applications, can be imparted with unique and useful performance properties, to improve structural performance.
Abstract:
A heat-resistant fiber paper-like sheet comprises 40 to 97% by mass of heat-resistant organic synthetic polymers staple fibers, 3 to 60% by mass of heat resistant organic synthetic polymer fibrid and or an organic resin binder, in a portion of the staple fibers, each staple fiber having two flat end faces having an inclining angle of 10 degrees or more from a plane crossing the fiber axis at a right angles, and is useful as a base material for laminate materials for electrical circuit boards.
Abstract:
The present invention relates to a nonwoven substrate, and specifically to a nonwoven substrate imparted with a three-dimensional image, wherein the three-dimensional nonwoven substrate is particularly suited as a support substrate for a PCB (printed Circuit Board) and similar application. The nonwoven substrate is formed from a precursor web (P) which undergoes entangling treatment by entangling manifolds (16, 20, 24'). By the utilization of a hydroentangled, three-dimensionally imaged support substrate impregnated with a durable resinous matrix, PCB's, and similar applications, can be imparted with unique and useful performance properties, to improve structural performance.
Abstract:
A heat-resistant fiber paper sheet which is formed from staple fibers made from a heat-resistant organic polymer, undrawn or low ratio drawn para-aromatic polyamide staple fibers, and an organic resin binder and/or fibrids comprising a heat-resistant organic polymer as main components, wherein the amount of said staple fibers is 45 to 97 percent by weight based on the total amount of said heat-resistant fiber paper sheet; the total amount of said organic resin binder and/or said fibrids is 3 to 55 percent by weight based on the total amount of said heat-resistant fiber paper sheet; and said organic resin binder is cured, and/or said undrawn or low ratio drawn para-aromatic polyamide staple fibers and said fibrids are partially sòftened, deformed and/or melted to exhibit the actions of binders. The obtained heat-resistant fiber paper sheet has excellent heat resistance, excellent heat dimensional stability, excellent plybond strength, an excellent electric insulating property in a high humidity, and the like, has good resin impregnability in spite of having a high bulk density, and is especially suitable for use as a substrate for electric insulating materials or as a substrate for laminates used for electric circuits.
Abstract:
A type of fiber paper is provided that is made of completely aromatic polyamide fiber formed by means of liquid crystal spinning. The fiber paper can be used as the base material of a substrate for electric circuit, and it can display high reliability in electric insulation under a high humidity, excellent post-heating dimensional stability, and high heat resistance.
Abstract:
A nonwoven fabric is constructed of a highly flat glass fiber which is a glass fiber whose section is flat and has a flatness ratio of 2.0 to 10 and which has such a section that the packing fraction is at least 85%, preferably at least 90%. In this nonwoven fabric, the glass fiber section has a shape near rectangle, and hence, the glass fibers can be arranged very densely to form a thin nonwoven fabric having a high bulk density, and when it is used as a laminate material, the glass fiber content can be increased and the surface smoothness can simultaneously be enhanced and can be used appropriately as a reinforcing material for a printed wiring board. Moreover, the above flat glass fiber can be produced by use of, for example, a nozzle having such a shape that one side of the major axis walls of a nozzle chip having a flat nozzle hole is partly notched.
Abstract:
There are disclosed a nonwoven reinforcement for a printed wiring base board which nonwoven reinforcement comprises a wet-system nonwoven fabric constituted of thermotropic cystalline polyester fiber having a melting point of 290°C or higher( component A ) and a thermotropic cystalline polyester binder which has a melting point of 290°C or higher and is in the form of a film having holes including at least 5 holes /mm 2 each with an area of opening of 400 to 10000 µm 2 ( component B ), the component A being fixed by the component B; a process for producing the above nonwoven reinforcement; a printed wiring base board produced from the above nonwoven reinforcement; and a printed wiring board produced from the above printed wiring base board. The nonwoven reinforcement and the printed wiring ( base) board are excellent in various performances such as uniformity, dimensional stability, heat resistance and electrical characteristics such as dielectric constasnt and dielectric loss tangent.