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 fibre 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 incorporating the coated fabric strand and an electronic support and an electronic circuit board incorporating the fabric.
Abstract:
The present invention provides a coated fiber strand comprising at least one fiber having a layer of a dried residue of a resin compatible coating composition on at least a portion of a surface of the at least one fiber, the resin compatible coating composition comprising: a) a plurality of discrete, dimensionally stable particles formed from materials selected from the group consisting of organic materials, polymeric materials, composite materials and mixtures thereof that provide an interstitial space between the at least one fiber and at least one adjacent fiber, the particles having an average particle size of about 0.1 to 5 micrometers; b) at least one lubricious material; c) at least one polymeric film former; and d) at least one coupling agent, and a fabric incorporating at least one of the fiber strands.
Abstract:
A pre-preg substrate, having a low dielectric constant and containing a substantially uniformly distributed hollow-glass-microsphere filler, and method for making the same. The pre-preg substrate is treated with impregnation and lamination techniques to form a laminate with a low dielectric constant, and good mechanical and electrical properties, suitable as a base material for surface mounted devices in high performance circuits. Improved pre-pregs for making high performance circuit boards and for making surface mounted integrated circuits. Improved high performance circuit boards for making surface mounted integrated circuits.
Abstract:
A method for fabrication of a circuit board laminate (10) in a continuous process employs an extruded laminate core (12). Streams of a fibrous material, microspheres or fused silica, a catalyst and a thermosetting resin are added to an extruder and the core extruded as a film; outer layers (18, 19) can be applied to the extruded core.
Abstract:
A printed circuit assembly (10) and method of making the same utilize in one embodiment an adhesive layer (40) including a plurality of non-conductive "gauge particles" (44) disposed within a non-conductive adhesive (42). When the adhesive layer (40) is disposed between opposing printed circuit layers (20, 30) (be they insulating substrates, conductive layers, or other layers), individual gauge particles (44) are interposed or sandwiched at various points between the layers such that the diameters of the particles control the layer separation throughout overlapping areas thereof, thereby permitting careful control over layer separation. A printed circuit assembly and method of making the same utilize in another embodiment an interlayer interconnecting technology incorporating conductive posts that are deposited on one of a pair of contact pads formed on opposing printed circuit boards and thereafter bonded to the other in the pair of contact pads during lamination. Fusible material may be utilized in the conductive posts to facilitate mechanical bonding to a contact pad, and the posts project through a dielectric layer disposed between the printed circuit boards, thereby forming the electrical connections between the boards at discrete locations.
Abstract:
PROBLEM TO BE SOLVED: To provide a B-stageable or preformed underfill encapsulant composition. SOLUTION: A composition of the present invention contains a resin system comprising a thermoplastic or thermosetting resin, an expandable microsphere, a solvent, and optionally a catalyst. Various other additives such as adhesion promoters, flow additives, and rheology modifiers may also be added as desired. The underfill encapsulant can be B-staged to provide a coating on a substrate or a component that is smooth and non-tacky. In an alternative embodiment, the underfill encapsulant is a preformed film. In both embodiments, application of higher temperatures makes the expandable filler material expand to form a closed cell structure in a desired portion of an assembly. COPYRIGHT: (C)2007,JPO&INPIT