306 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 (S_in) 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 (Z_L) connected at the receiving end of the cable, and the characteristic impedance (Z_O) 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 (Z_L) 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 (Z_L), 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.

A UV-curable acrylate-thiol-ene insulating coating composition for electrical conductors, a method of manufacturing a UV-curable acrylate-thiol-ene insulating coating composition for electrical conductors. The insulating coating being of about 2.5 mum to about 500 mum thickness, which cured coating has a dielectric dissipation factor (60Hz, 24° C.) of lower than about 0.05.

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.

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.

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.

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.

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.

The invention provides a key management system of a prepayment meter, which comprises a root key card management subsystem, a master key card management subsystem, and an application card management subsystem; the root key card management subsystem issues a root key card; after the master key card management subsystem adds area identity dissipation factors to the root key management card, the root key card educes the master key card for specially issuing work according to the area dissipation; the application card management subsystem imports the master key card in the application card. The key management system of the prepayment device has the advantages that: a three-level manner is adopted to issue and deliver the key to guarantee the confidentiality; the key management system of the prepayment meter keeps independent running from the management system of selling electricity, water, gas, and the like; the parent card and the application card have the same type; as the area factors are added to the keys, whether the application card in various areas is compatible or not, the system can be flexibly controlled.