Abstract: Crosslinkable liquid crystalline polymer compositions for use as dielectric materials in circuit materials, circuits, and multi-layer circuits are disclosed. The crosslinkable liquid crystalline polymer compositions comprise crosslinkable liquid crystalline polymers that preferably comprise end groups selected from the group consisting of phenyl maleimide, nadimide, phenyl acetylene, or combinations of the foregoing. Additionally, the crosslinkable liquid crystalline polymer compositions may further comprise particulate fillers and/or fibrous webs. The crosslinkable liquid crystalline polymer compositions provided improved electrical and mechanical properties.

Abstract: A liquid crystalline composite comprising a liquid crystalline polymer, particulate filler, and fibrous web. Further disclosed is a method for forming the liquid crystalline polymer composite. The liquid crystalline polymer composite is useful in circuit materials, circuits, and multi-layer circuits, economical to make, and has excellent flame retardant properties.

Abstract: A liquid crystalline composite comprising a liquid crystalline polymer, particulate filler, and fibrous web. Further disclosed is a method for forming the liquid crystalline polymer composite. The liquid crystalline polymer composite is useful in circuit materials, circuits, and multi-layer circuits, economical to make, and has excellent flame retardant properties.

Abstract: A method of making a bond ply comprises treating a film comprising a liquid crystalline polymer with an amount of heat and pressure effective to produce a liquid crystalline polymer bond ply with an in-plane coefficient of thermal expansion (CTE) of 0 to about 50 ppm/° C. Such bond plies are of particular utility in the manufacture of circuit boards.

Abstract: A multi-layer circuit board comprises a liquid crystalline polymer bond ply disposed between two circuit layers wherein the liquid crystalline polymer bond ply is formed by treating a film comprising a liquid crystalline polymer with an amount of heat and pressure effective to produce a liquid crystalline polymer bond ply with an in-plane coefficient of thermal expansion (CTE) of 0 to about 50 ppm/° C. and further wherein the multi-layer circuit is formed by lamination at a temperature of 0° C. to about 10° C. less than the melt temperature of the liquid crystalline polymer.

Abstract: Articles are formed from a thermosetting composition based on polybutadiene or polyisoprene resins which are subjected to a high temperature cure step of greater than 250° C. The thermosetting compositions may include fillers such as particulate ceramic fillers and may also include woven webs for improved dimensional stability and decreased brittleness. The formation process of this invention is particularly well suited for making electrical circuit substrates for microwave and digital circuits, typically in the form of the thermosetting composition being laminated on one or both opposed surfaces to metal conductive foil (e.g., copper).

Abstract: A load beam for a suspension assembly comprises a liquid crystal polymer layer disposed between and in intimate contact with a first metal layer and a second metal layer, preferably stainless steel. Such load beams have improved dimensional and hygrothermal stability, as well as greater ease of processing over conventional load beams, allowing tailoring of bend and flex properties.

Abstract: A multi-layer circuit comprises a circuit and a resin covered conductive layer disposed on the circuit, wherein the resin covered conductive layer comprises a liquid crystalline polymer resin laminated to a conductive layer. Such multi-layer circuits are particularly useful for high density circuit applications.

Abstract: A load beam for a suspension assembly comprises a liquid crystal polymer layer disposed between and in intimate contact with a first metal layer and a second metal layer, preferably stainless steel. Such load beams have improved dimensional and hygrothermal stability, as well as greater ease of processing over conventional load beams, allowing tailoring of bend and flex properties.

Abstract: A multi-layer circuit comprises a circuit and a resin covered conductive layer disposed on the circuit, wherein the resin covered conductive layer comprises a liquid crystalline polymer resin laminated to a conductive layer. Such multi-layer circuits are particularly useful for high density circuit applications.

Abstract: A multi-layer circuit board comprises a liquid crystalline polymer bond ply disposed between two circuit layers wherein the liquid crystalline polymer bond ply is formed by treating a film comprising a liquid crystalline polymer with an amount of heat and pressure effective to produce a liquid crystalline polymer bond ply with an in-plane coefficient of thermal expansion (CTE) of 0 to about 50 ppm/° C. and further wherein the multi-layer circuit is formed by lamination at a temperature of 0° C. to about 10° C. less than the melt temperature of the liquid crystalline polymer.

Abstract: The present invention is a liquid crystal polymer suspension assembly. This assembly comprises a stainless steel layer and an electrically conductive layer with a dielectric liquid crystal polymer layer disposed therebetween and bonded thereto. Due to controlled coefficient of thermal expansion, modulus, and very low moisture absorption of the liquid crystal polymer, the suspension assembly of the present invention will have improved dimensional and hygrothermal properties over conventional assemblies, enabling higher density, higher performance assemblies to be produced.

Abstract: An electrical substrate material is presented comprising a thermosetting matrix of polybutadiene or polyisoprene in an amount of about 15 to about 50 volume %; a fabric reinforcement in an amount of 0 to about 40 volume %; a particulate filler, preferably ceramic, in an amount of from 0 to about 60 volume %; microballoons in an amount from 0 to about 60 volume %; and optionally a flame retardant. A peroxide cure initiator and/or crosslinking agent may optionally be added. The presence of a very high surface area particulate filler, preferably fumed silica, is also preferred, in that its presence results in a prepreg which has very little tackiness and can therefore be easily handled by operators. This low tackiness feature allows for the use of conventional automated layup processing, including foil cladding, using one or more known roll laminators.

Abstract: An electrical substrate material is presented comprising a thermosetting matrix of polybutadiene or polyisoprene and a co-curable second resin distinct from the first resin. A peroxide cure initiator and/or crosslinking agent may optionally be added. The presence of a very high surface area particulate filler, preferably fumed silica, is also preferred, in that its presence results in a prepreg which has very little tackiness and can therefore be easily handled by operators. This low tackiness feature allows for the use of conventional automated layup processing, including foil cladding, using one or more known roll laminators. While the prepreg of this invention is tack-free enough to be handled relatively easily by hand, it is also tacky enough to be tacked to itself using a roll laminator (e.g., nip roller) at room temperature.

Abstract: An electrical substrate material is presented comprising a thermosetting matrix of polybutadiene or polyisoprene in an amount of 25 to 50 volume %; a woven glass fabric in an amount of 10 to 40 volume %; a particulate, preferably ceramic filler, in an amount of from 5 to 60 volume %; and a flame retardant. Importantly, the composition comprises only a single resin, i.e., polybutadiene or polyisoprene. A peroxide cure initiator and/or crosslinking agent may optionally be added. The presence of a very high surface area particulate filler, preferably fumed silica, is also preferred, in that its presence results in a prepreg which has very little tackiness and can therefore be easily handled by operators. This low tackiness feature allows for the use of conventional automated layup processing, including foil cladding, using one or more known roll laminators.

Abstract: An electrical substrate material is presented which comprises a thermosetting matrix which includes a polybutadiene or polyisoprene resin and an unsaturated butadiene or isoprene containing polymer in an amount of 25 to 50 vol. %; a woven glass fabric in an amount of 10 to 40 vol. %; a particulate, preferably ceramic filler in an amount of from 5 to 60 vol. %; a flame retardant and a peroxide cure initiator. A preferred composition has 18% woven glass, 41% particulate filler and 30% thermosetting matrix. The foregoing component ratios and particularly the relatively high range of particulate filler is an important feature of this invention in that this filled composite material leads to a prepreg which has very little tackiness and can therefore be easily handled by operators. This low tackiness feature allows for the use of conventional automated layup processing, including foil cladding, using one or more known roll laminators.

Abstract: A high dielectric (K'.gtoreq.5), comparatively low thermal coefficient (absolute value of TCK'.ltoreq.200 ppm/.degree.C.) polymeric composite matrix is presented comprising commonly available and low cost fillers such as titania, alumina and magnesium oxide.