314 results about "Dissipation factor" patented technology

A polyphenylene oxide resin belongs to a polymerized and / or modified thermosetting polyphenylene oxide resin, having a structure represented by formula (I):The polymerized and / or modified thermosetting polyphenylene oxide resin has better flame retardancy, thermal resistance, dielectric constant, dissipation factor, toughness, reactivity, viscosity and solubility. Therefore, the polyphenylene oxide resin is suitable for producing prepregs, resin films, laminates, printed circuit boards and other articles. A method of preparing polyphenylene oxide resins, a prepolymer thereof and a resin composition containing the polyphenylene oxide resin are also provided.

Cable diagnostic test methods, systems and apparatus are disclosed that utilize “standing wave” principles to facilitate identification and location of insulation defect(s) along a power cable. The methods / systems measure dissipation factors and dielectric constants associated with the power cable insulation and the impedance of the power cable conductor at any number of points or sections along the axial length of the cable. In an exemplary embodiment, the disclosed method involves (i) connecting an alternating voltage source to a cable at a “sending end” thereof; (ii) applying a voltage to the cable at a first frequency to set up a traveling wave along the cable that is reflected at the “receiving end” thereof; (iii) permitting a standing wave pattern to be established along the cable by the traveling wave and the reflection thereof; (iv) measuring the total complex power loss (Sin) at the sending end of the cable; (v) calculating the standing wave voltage at any point / section of the cable based on the load impedance (ZL) connected at the receiving end of the cable, and the characteristic impedance (ZO) of the cable, or the measured / calculated cable parameters for the first frequency of the voltage source, (vi) repeating the foregoing steps while one of: (1) varying at least one of: the load impedance (ZL) connected at the receiving end of the cable, the first frequency of the voltage source; the output impedance of the voltage source, a combination of the load impedance (ZL), the output impedance of the voltage source and the first frequency of the voltage source, and combinations thereof; (2) interchanging sending and receiving cable ends; and (3) a combination thereof, and (vii) determining a dissipation factor (tan δ) and a dielectric constant (∈′), for the insulation, and an impedance, for the conductor at predetermined points / sections along the axis of the cable.

A solid electrolytic capacitor that comprises an anode that contains a valve-action metal (e.g., tantalum, niobium, and the like) and a dielectric film overlying the anode is provided. The capacitor also comprises a protective coating overlying the dielectric film, wherein the protective coating contains a relatively insulative, resinous material. For example, in one embodiment, the resinous material can be a drying oil, such as olive oil, linseed oil, tung oil, castor oil, soybean oil, shellac, and derivatives thereof. The capacitor also comprises a conductive polymer coating overlying the protective coating. As a result of the present invention, it has been discovered that a capacitor can be formed that can have a relatively low leakage current, dissipation factor, and equivalents series resistance.

The present invention discloses a thermosetting resin composition comprising: a bifunctional or multifunctional epoxy resin, a styrene-maleic anhydride (SMA) copolymer with a styrene / maleic anhydride molar ratio of 5-12:1 as a curing agent, a BPA epoxy resin with a low or high bromine content or tetrabromobisphenol A as a flame retardant agent, an accelerator and a solvent. The cured resin composition of the invention has a very low dielectric property, improved thermal reliability and better toughness. A copper clad laminate made of the resin composition and a reinforced material such as glass fiber cloth has a very low dielectric constant and dissipation factor, high Td, better toughness and PCB manufacturability, and thus very suitable to be used as a copper clad laminate and a prepreg for manufacturing PCBs and also applied to the common use of epoxy resins, such as molding resins, and composite materials for construction, automobiles and aviation.

High oleic acid triglyceride compositions that comprise fatty acid components of at least 75% oleic acid, less than 10% diunsaturated fatty acid component; less than 3% triunsaturated fatty acid component; and less than 8% saturated fatty acid component; and having the properties of a dielectric strength of at least 35 KV / 100 mil gap, a dissipation factor of less than 0.05% at 25NC, acidity of less than 0.03 mg KOH / g, electrical conductivity of less than 1 pS / m at 25NC, a flash point of at least 250NC and a pour point of at least −15NC are disclosed. Electrical insulation fluids comprising the triglyceride composition are disclosed. Electrical insulation fluids that comprise the triglyceride composition and a combination of additives are disclosed. Electrical apparatuses comprising the electrical insulation fluids and the use of electrical insulation fluids to provide insulation in electrical apparatuses are disclosed. A process for preparing the high oleic acid triglyceride composition is disclosed.

Multilayer ceramic chip capacitors which satisfy COG requirements and which are compatible with reducing atmosphere sintering conditions so that non-noble metals such as copper and copper alloys thereof may be used for internal and external electrodes are made in accordance with the invention. The capacitors exhibit desirable dielectric properties (high capacitance, low dissipation factor, high insulation resistance), excellent performance on highly accelerated life testing, and very good resistance to dielectric breakdown. The dielectric layers comprise a composite oxide formed by calcining rare earth titanates, barium titanate, together with other metal oxides such as MgO, CaO, ZnO, MnO2, ZrO2, SiO2, Ga2O3, Nd2O3, Nb2O5, and Y2O3.

A mold for uniformly heating working material to form a workpiece using a microwave oven. Uniform heating of a workpiece of variable thickness may be obtainied in a microwave oven with a uniform electric field in its cavity if the mold material is selected to have a dielectric constant and a thermosensitivity equal to that of the working material. The thermosensitivity of a material is its dissipation factor divided by the product of its density and specific heat. Uniform heating of a uniformly thick workpiece can be obtained in a conventional microwave by selecting the mold material to have a relative thermosensitivity equal to that of the working material. The relative thermosensitivity of a material is its dissipation factor divided by the product of its dielectric constant, density, and specific heat.

The invention is an electrically conductive device, e.g., a wire or cable, having a crush resistance of at least about 18 pounds per square inch (psi), the device comprising: A. An electrically conductive member comprising at least one electrically conductive substrate, e.g., a wire strand or a pair of twisted wire strands; and B. At least one electric-insulating member substantially surrounding the electrically conductive member, e.g., a polymer coating or layer, the electric-insulating member comprising a polymer blend, the polymer blend comprising: 1. At least about 50 weight percent of a polypropylene, and 2. At least about 10 weight percent of an elastomer. In one embodiment, the blend is characterized as having (i) a hot creep of less than 200% at 150 C, (ii) a dielectric constant at 60 Hz and 90 C of less than about 2.5, (iii) a dissipation factor at 60 Hz and 90 C of less than about 0.005, and (iv) an AC breakdown strength of greater than about 600 v / mil.

An electrical circuit material having a conductive layer disposed a substrate, wherein the substrate comprises an organic or inorganic polymer comprising a covalently bound polyhedral silsesquioxane (POSS). The substrate may further comprise an additional dispersed POSS, any other fillers including fibrous webs. Use of covalently bound POSS allows for flame retardancy in compositions having acceptable dielectric constants and dissipation factors.

Curable functionalized imide-linked polyimides compounds have been synthesized that have been found to possess very low dielectric constant and extremely low dissipation factor. These compounds also have a range of high to low modulus, extremely low moisture uptake and are very thermally stable. The combination of these materials in formulation along with functionalized polyethylene, polypropylene, polybutadiens have been found to be ideal for forming films and coatings for the microelectronic applications, multiplayer capacitors and interconnects, and high power cables and wire coatings. The addition of perfluorinated hydrocarbons, and POSS nanoparticles to the formulations have decreased the dielectric constant and dielectric dissipation factor further, and have also improved the flammability of the compositions.

A method of forming a circuit material comprises disposing an adhesion promoting elastomer composition between a conductive copper foil and a thermosetting composition; and laminating the copper foil, adhesion promoting composition, and thermosetting composition to form the circuit material. The adhesion promoting layer may be uncured or partially cured before contacting with the curable thermosetting composition. Preferably the adhesion promoting layer has electrical characteristics such as dissipation factor, dielectric breakdown strength, water absorption, and dielectric constant that are similar to and / or compatible with the electrical characteristics of the thermosetting composition.

The invention relates to a thermosetting resin composition and a prepreg and a laminate for printed circuits thereby. The thermosetting resin composition comprises at least an epoxy resin with a component being the structural formula (I) and a curing agent. The molecular structure of the epoxy resin composition of the invention contains the low-polarity styrene structure, therefore, the dielectricproperty of the resin is optimized. The dielectric constant and the dielectric loss angle tangent are reduced compared with those of the common epoxy resins. The prepreg obtained by coating the resincomposition on the substrates and the laminate manufactured by laminating the prepreg simultaneously have the characteristics of low dielectric constant, low dielectric dissipation factors, good heatresistance, good dip soldering resistance, good moisture resistance, good humidity resistance and good cohesiveness with copper foils. The resin composition of the invention can be also used for manufacturing the resin sheets, resin composition copper foils, the laminate and the printed circuit boards. R is (a), and n and m are natural numbers.

The invention provides a low dielectric PBT / PETG alloy nanometer injection molding composite material as well as a preparation method and application thereof. The preparation raw materials of the PBT / PETG alloy nanometer injection molding composite material comprise the following components in parts by weight: 30 to 50 parts of PBT resin, 30 to 50 parts of PETG resin, 30 to 40 parts of glass fiber, 0.2 to 0.8 part of an antioxidant, 1 to 2 parts of a lubricating agent, 0.3 to 0.5 part of an anti-UV agent and 3 to 8 parts of a compatilizer. The PBT / PETG alloy nanometer injection molding composite material has high mechanical performance, heat resistance, chemical resistance and machinability, has relatively low dielectric constant and relatively low dielectric dissipation factor, and is applicable to the preparation of low dielectric materials or electric equipment products.

Laminates have at least one resin-system layer, a low dielectric, low dissipation factor bond core having at least one surface that is treated for adhesion, such as by etching, plasma or Corona discharge or mechanical roughing to facilitate bonding to the at least one resin system layer and a conductive metal cladding on the at least one resin system layer. The bond core can be a fluoropolymer film or a fluoropolymer prepreg, having at least one etched or Corona discharge treated surface. Alternately, the bond core can be a polyetherimide film or a polyetherimide prepreg, having at least one etched or Corona discharge treated surface. The laminates are used, for example, high performance, low loss printed circuit boards. The laminates have the desired dielectric properties inherent to fluoropolymer materials and can be produced using conventional printed circuit board manufacturing processes, materials, and equipment. Methods of producing laminates are disclosed.

Novel additive systems for metallocene based filled cable insulation are disclosed. These systems provide excellent protection against thermal degradation, better cure state and reduced dissipation factor after prolonged heat exposure. The additives may contain one or more hindered amine light stabilizers and amine antioxidants.

The present invention relates to a thermosetting low dielectric resin composition, a laminate for use in printed wiring, a laminate for a circuit, and the like. The present invention's thermosetting low dielectric resin composition contains a specific siloxane denatured polyimide, a compound having two or more allyl or methylallyl groups, and a compound having two or more maleimide groups. This resin composition adheres extremely well to metals with a low dielectric constant and low dielectric dissipation factor, and demonstrates very little scattering of the resin during operational processes like punching or cutting. By using laminates or laminates for circuits that employ this resin composition, electrical signals can be propagated more quickly, enabling signals to be processed at faster speeds. In addition, the present invention can be applied to the formation of miniaturized circuit wiring, and is suitably employed in electronic devices employed in the high frequency region, and, in particular, in electronic devices that must be made smaller and lighter in weight.

The invention discloses a polymer modified graphene / polyvinylidene fluoride high-dielectric composite material and a preparation method thereof. The composite material is prepared by taking polyvinylidene fluoride as a matrix and taking graphene subjected to graft modification by aminosilane and polymer sequentially as dielectric enhancement functional filler through solution blending, electrostatic spinning and laminar hot-press molding sequentially. On the basis of dual regulation of interface and spatial microstructures, uniform dispersion of high-filling-volume graphene filler in the polyvinylidene fluoride matrix is effectively realized according to a graphene surface polymer grafting modification and electrostatic spinning combined method, and the dielectric constant of the obtainedgraphene / polyvinylidene fluoride composite material is evidently increased while a small dielectric dissipation factor is achieved, so that the polymer modified graphene / polyvinylidene fluoride high-dielectric composite material is applicable to fields of embedded capacitors, high-energy-density energy accumulators and the like.

A circuit substrate laminate, comprising a conductive metal layer; and a dielectric composite material having a dielectric constant of less than about 3.5 and a dissipation factor of less than about 0.006, wherein the dielectric composite material comprises: a polymer resin; and about 10 to about 70 volume percent of cenospheres having a ferric oxide content of less than or equal to 3 weight percent.

The composite dielectric of the present invention contains an aromatic liquid crystal polyester and a dielectric ceramic powder arranged in the aromatic liquid crystal polyester, wherein the dielectric ceramic powder exhibits a Q value greater than 650 at a frequency of 1 GHz by perturbation. A wiring board comprising a composite dielectric sheet made of a composite dielectric having such a characteristic exhibits a high dielectric constant and a low dielectric dissipation factor, thereby yielding less transmission loss, and thus can favorably be used in electronic instruments driven in high-frequency regions.

A method of forming a circuit material comprises disposing an adhesion promoting elastomer composition between a conductive copper foil and a thermosetting composition; and laminating the copper foil, adhesion promoting composition, and thermosetting composition to form the circuit material. The adhesion promoting layer may be uncured or partially cured before contacting with the curable thermosetting composition. Preferably the adhesion promoting layer has electrical characteristics such as dissipation factor, dielectric breakdown strength, water absorption, and dielectric constant that are similar to and / or compatible with the electrical characteristics of the thermosetting composition.

The invention relates to a high frequency nickel-copper-zinc ferrite and a method for preparing the same, which belong to the technical field of nickel series soft magnetism ferrite. The main components of the ferrite are ferric oxide, nickel oxide, zinc oxide, and copper oxide, the accessory components comprise cobalt oxide, bismuth oxide, and silicon oxide, and the ferrite is prepared by an oxide method. The invention adopts an iron deficiency formulation, a low calcination temperature, and a low sintering temperature so that the prepared high frequency nickel-copper-zinc ferrite has good performances of low initial permeability, low relative dissipation factor between 50MHz and 200MHz, and high Curie temperature, and can better satisfy the use requirement of communication electronic parts and components; besides, the preparation process is stable, and the production process has low energy consumption.

This invention relates to a low dielectric resin varnish composition for laminated printed circuit boards, wherein the resin composition includes (A) Dicyclo-pentadiene-Phenolic Novolac resin (abbreviated as DCPD-PN); or (B) at least one kind of dicyclopentadiene Phenolic Novolac Epoxy resins(DCPD-PNE, referred to as Resin 1); or (C) a novel Dicyclopentadiene-Dihydrobenzoxazine resin (DCPD-BX, referred to as Resin 2); or the mixture of (B) and (C), and (D) Flame retardant agent, curing agent and accelerating agent solutions.Because all of component (A) DCPD-PN, component (B) DCPD-PNE and component (C) DCPD-BX in this resin varnish composition contain a saturated multi-cyclic structure of dicyclopentadiene, the resin varnish shows lower dipole, dielectric constant (Dk), dissipation factor (Df) and moisture absorption; and via adding a brominated or phosphorus flame retardant, the composition exhibits high thermal stability characteristic. The copper clad laminates obtained in accordance with the invention meet not only the demand of low dielectric constant (Dk<4.0 @ 1 GHz) and low dissipation factor (Df<0.009 @ 1 GHz), but also possesses high heat stability and low moisture absorption characteristics, thus are widely applied to high-performance electronic materials.

A circuit subassembly is disclosed comprising a conductive metal layer and a dielectric substrate layer having a dielectric constant of less than about 3.5 and a dissipation factor of less than about 0.006 at 10 GHz, wherein the composition of the dielectric substrate layer comprises about 5 to about 70 volume percent of borosilicate microspheres that have been treated with an alkaline solution.

An object is to provide a molded product, which has dielectric properties that the conventional liquid crystal polyester resin has not realized, and simultaneously which keeps a heat resistance such as solder reflow of a liquid crystal polyester, and which is used in information and telecommunications equipment employed in high frequency band regions such as microwaves and millimeter waves. A molded product of a wholly aromatic liquid crystal polyester resin composition which has a dielectric constant of 3.0 or less and a dielectric dissipation factor of 0.04 or less and which is obtained by an injection molding of a composition comprising 90 to 45 percent by weight of the wholly aromatic liquid crystal polyester having a melting point of 320° C. or more, 10 to 40 percent by weight of an inorganic spherical hollow material having an aspect ratio of 2 or less, and 0 to 15 percent by weight (100 percent by weight in total) of an inorganic filler having an aspect ratio of 4 or more. The molded product of the present invention has dielectric properties suitable for information and telecommunications equipment, and is excellent in solder heat resistance, processability, and dimensional stability so that the molded product is advantageous as a substrate material for use in information and telecommunications equipment such as a cellular mobile phone and as a fixing or a holding member of a transmitter-receiver element.

The present invention provides a halogen-free flame retardant resin composition, and, a prepreg, a laminate, and a laminate for printed circuit that are made from the halogen-free flame retardant resin composition. The halogen-free flame retardant resin composition comprises: (A) 40-80 parts by weight of the mixture of a phenoxyphosphazene compound (A1) and a dihydrobenzoxazine ring-containing compound (A2), and, the weight ratio between the phenoxyphosphazene compound (A1) and the dihydrobenzoxazine ring-containing compound (A2) being between 1:10 and 1:2; (B) 15-45 parts by weight of a polyepoxy compound; (C) 5-25 parts by weight of a phenolic resin type hardener; and (D) 0.1-1 parts by weight of an imidazole type compound as the curing accelerator. The prepreg, the laminate, and the laminate for printed circuit that are made from the halogen-free flame retardant resin composition provided by the present invention, have excellent flame retardancy, as well as has high glass transition temperature (Tg), high thermal resistance, high flexural strength, high reliability, low dielectric dissipation factor, low moisture, low C.T.E, good chemical resistance, and good processability.

A halogen-free resin composition includes 100 parts by weight of epoxy resin; 10 to 100 parts by weight of benzoxazine resin; 10 to 100 parts by weight of styrene-maleic anhydride copolymer; and 10 to 90 parts by weight of dicyclopentadiene phenol novolac resin. The halogen-free resin composition features specific ingredients and proportions thereof to attain low dielectric constant (Dk), low dielectric dissipation factor, high heat resistance and high non-flammability and produce prepregs or resin film, and is thus applicable to copper clad laminates and printed circuit boards.

The invention discloses a signal processing and calculating method for insulation dielectric dissipation factors with the characteristics of high precision and immunity to electromagnetic interference, which developed by aiming at high-voltage electric-power capacitive equipment for realizing insulation online monitoring technology in the equipment life cycle management of an intelligent power grid. In the scheme, based on distributing type remote synchronous signal collection and through carrying out complete-frequency discrete sampling on the leakage current and the busbar voltage of the high-voltage capacitive equipment in a timing way, an infinite impulse response filter group (IIRG) consisting of a point-pass filter, a low-pass filter, a high-pass filter and a necessary point-resistance filter is arranged by aiming at the interference characteristics of high-voltage electric power equipment, input signal sequences adaptive to the time constants of the IIRG are obtained through signal extension, filter output with 50Hz of power frequency signals is obtained through the IIRG, the phasor phase difference of the leakage current and the busbar voltage of the high-voltage capacitive equipment are obtained with a phase algorithm, and further the insulation dielectric dissipation factors with high precision are obtained.

A magnetic toner which has superior charging stability and charging uniformity, maintains stable developing performance without any dependence on service environments and may less cause any decrease in image density and any image defects such as fog and ghost, the magnetic toner has magnetic toner particles, each of the magnetic toner particles has magnetic toner base particle containing a binder resin and a magnetic material, and an inorganic fine powder, (a) the magnetic toner having, at a frequency of 100 kHz and a temperature of 30° C., a dielectric loss factor (∈″) of 2.5×10−1 pF / m or more and 7.0×10−1 pF / m or less and a dielectric dissipation factor (tan δL) of 3.0×10−2 or less, (b) the magnetic toner having, in a dielectric dissipation factor (tan δ) thereof at a frequency of 100 kHz, a maximum value (tan δH) within the temperature range of 60° C. to 140° C.; and the tan δH and the tan δL satisfying (tan δH−tan δL)≦3.0×10−2.

An apparatus for monitoring the integrity of a wire is provided, which includes a TDR instrument for generating a pulse waveform for transmission through the wire. The apparatus also includes a function generator for generating an electrical or non-electrical forcing waveform for transmission through the wire. The pulse waveform is transmitted through the wire in combination with the forcing waveform and a detector measures a change in dissipation factor values along the wire.