1894results about How to "Improve thixotropy" patented technology

The invention discloses an attapulgite argil powder with an air purifying function. The technical scheme is as follows: the attapulgite argil powder with an air purifying function is prepared from high-viscosity attapulgite clay, an attapulgite constant-humidity conditioner, a natural mineral adsorbing / filtering agent, Cacumen Biotae, aluminum silicate fiber and polyacrylamide. The attapulgite argil powder is prepared by the following steps: pulverizing the materials, soaking and aging to obtain a wet mixture, extruding the wet mixture into a strip, airing the strip, pulverizing to obtain powder, and packaging to obtain the finished product. The attapulgite argil powder has favorable cohesive property, plasticity, thixotropy, fire resistance and thermal stability; the pottery prepared from the attapulgite argil powder with an air purifying function contains a great deal of micropores and activated carbon, thus, has the characteristics of low shrinkage, no cracking or deformation and favorable adsorbability, and can effectively adsorb formaldehyde, ammonia, benzene and other harmful substances in the air, thereby protecting the environment and improving good health of people. The invention is suitable for producing pottery artware with an air purifying function.

The invention discloses electric conductive silver paste and a manufacturing method of the electric conductive silver paste. The electric conductive silver paste comprises, by mass percentage, 35 - 65 % of micron-sized silver powder, 1-10 % of nanometer-sized silver powder of or 1-20 % of nanometer-sized silver and other metal alloy powder, and 1-10 % of an organic carrier; for ceramics, solar cell silver paste comprises 2-15 % of unleaded glass powder, each component is manufactured in parts, weighed, mixed and stirred or mixed and rapidly scattered, and ultrasonic-vibrated or fine adjusted of viscosity of solvent, and therefore the electric conductive silver paste is obtained. Due to the fact that the nanometer-sized silver powder or the nanometer-sized silver alloy powder is mixed with the micron-sized silver powder, intensity of conductivity and a circuit is improved, adhesive force of crushing resistance and a base plate is improved, at the same time unleaded slurry good in thixotropy, low in contacting resistance and low in piece-needed slurry amount replaces lead slurry materials, the electric conductive silver paste is used for manufacturing crystalline silicon solar cells, improves photoelectric conversion efficiency, accords with environmental-protection ideas, and can be produced in large scales continuously.

The invention relates to an auxiliary material for casting and moulding, in particular to a formula of alcohol group dry powder mold paint for sand mold casting. The dry powder mold paint comprises surface modifier, suspending agent, binder and refractory powder, wherein the surface modifier is 0.6-4.2wt% of refractory powder, the suspending agent is 4.0-8.0wt% of refractory powder and the binderis 4.0-6.2wt% of refractory powder. The alcohol group nanometer composite and surface modified dry powder mold paint of the invention adopts nanometer layered clay and nano-SiO2 to form composite suspending agent so that the controllability of operation technological parameters of the alcohol group dry powder mold paint is good and the process performance and operating performance of the obtainedpulp-type paint can both meet the demand of the casting factory.

A curable composition comprising (A) an organopolysiloxane having functional groups capable of condensation reaction at both molecular terminals thereof and (B-1) a hydrophobic silica and a hydrophilic silica. A curable composition comprising (A) an organopolysiloxane having functional groups capable of condensation reaction at both molecular terminals thereof and (B-2) a hydrophobic silica, wherein the hydrophobic silica (B-2) is thermally treated together with the organopolysiloxane (A). The organopolysiloxane (A) is preferably represented by the formula: W3-a(R1a)Si(R2)O-(Si(R2)O)n-Si(R1a)W3-a [alpha] (wherein W represents a hydroxyl group or a hydrolyzable group; each of R1 and R independently represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms, provided that the hydrocarbon groups R1 as well as the hydrocarbon groups R may be identical with or different from each other; n is an integer of 5 or greater; and a is 0, 1 or 2). When, in the formula [alpha], W represents a hydroxyl group and a is 2, the curable composition preferably comprises, in addition to the components (A) and either (B-1) or (B-2), (C) an organosilane represented by the formula: R1bSiX4-b [I] (wherein R1 represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms; X represents a hydrolyzable group; and b is 0 or 1), or a partial hydrolyzate of the organosilane. Thus, a curable composition, especially a curable paint composition and an antifouling paint composition, and an antifouling coating film of the following characteristics can be provided. The curable composition, in particular when used as a coating material or a paint, is excellent in sprayability and enables forming a thick coating film by one-time application. The curable composition enables shortening the operating period for coating, and a coating film of uniform thickness can be obtained by the application thereof. The obtained coating film is excellent in film strength and film hardness and, when used for antifouling purposes, exerts excellent antifouling capability for a prolonged period of time. Further, the curable composition ensures excellent storage stability before application thereof.

The invention relates to an automobile hemming adhesive and a preparation method thereof, belonging to the technical field of single-component epoxy adhesives. The automobile hemming adhesive is mainly used for bonding an automobile hemming part. The automobile hemming adhesive is mainly characterized by comprising (A) epoxy resin, (B) modified epoxy resin, (C) toughener, (D) epoxy diluter, (E) thermoplastic resin, (F) plasticizer, (G) thermal stabilizer, (H) latent curing agent, (I) coupling agent, (J) filler and (K) pigment. The preparation method comprises the following steps: (1) evenly stirring (E) and (F) at 5-35 DEG C; (2) adding the mixed liquid composition in the step (1), and (A), (B), (C), (D), (G), (H), (I), (J) and (K) into a movable mixer, and evenly stirring at 5-35 DEG C; (3) passing the mixture in the step (2) through a three-roller machine once or twice; and (4) vacuumizing the movable mixer, stirring, defoaming, and discharging for later use. The invention mainly solves the problems of low environmental-protection index, poor technical properties of sizing, short storage period, low modulus, poor moisture and heat resistance and the like in the existing hemming adhesive.

The invention discloses a lead-free and cadmium-free electrode silver slurry for piezoelectric ceramics. The lead-free and cadmium-free electrode silver slurry for piezoelectric ceramics is prepared from the following raw materials in percentage by weight: 50 to 75 percent of conducting silver micro powder, 0.5 to 5 percent of inorganic additive, 1 to 15 percent of lead-free glass powder and 15 to 45 percent of organic carrier. The lead-free and cadmium-free electrode silver slurry is technologically advantaged in that a boron-bismuth-silicon-zinc-titanium glass system is designed, the traditional lead-containing glass can be completely substituted, a lead-free product is realized, the system glass can react with a piezoelectric ceramic substrate to form a firm interface between an electrode and the substrate, and the adhesion force of the interface is more than 15N / mm<2>.

The invention relates to the technical field of soldering pastes, in particular to a halogen-free tin-bismuth-copper soldering paste and a preparation method thereof. A soldering flux of the halogen-free tin-bismuth-copper soldering paste consists of the following components in percentage by weight: 20 to 40 percent of polymerized rosin, 1 to 6 percent of rosin amine, 4 to 8 percent of thixotropic agent, 5 to 10 percent of organic acid, 5 to 10 percent of organic amine, 1 to 5 percent of antioxidant, 0.5 to 3 percent of surfactant and an organic solvent. The halogen-free tin-bismuth-copper soldering paste is mainly characterized by adopting the organic acid and the organic amine serving as activating agents and comprising no halogens at all, so not only the solderability is not reduced, but also the expansion rate and the insulation resistance value of the soldering paste are improved, and simultaneously the corrosivity of residues after soldering to a base material is reduced and the service life of the soldering paste is prolonged; and particularly, the peak temperature of the soldering paste during soldering is lower in favor of reducing the thermal damages to electronic components.

The invention discloses a preparation method of nano-calcium carbonate SCC-2 special for a silicone sealant, belonging to the technical field of inorganic chemical industry. According to an adopted technical scheme, the method comprises the following steps of: calcining limestone, crushing to obtain CaO; digesting, refining and aging the CaO in a hot state in the ratio of 1:4.8 of CaO to H2O; adding 1 percent of white granulated sugar crystal form control agent for undergoing a carbonation reaction to obtain CaCO3 slurry; performing activation surface treatment; and dehydrating, drying, crushing and degrading to obtain a nano-active CaCO3 product of 60-100 nanometers. The crystal form, size, regularity, oil absorption value and pH value of CaCO3 are controlled, so that 'hard aggregation' among particles is avoided from a surface modification production process, and the product has low oil absorption value and high bulk specific weight and has high dispersity in polymers.

The invention relates to the field of thermal interface materials, and more particularly, provides a thermal grease composition, which contains the following components: (A) 100.0 parts by weight of thermally conductive filler, (B) 0.1 to 8.0 parts by weight of active solid silicone resin, (C) 0.1 to 15.0 parts by weight of active silicone oil, (D) 0.1 to 9.0 parts by weight of macromolecular polysiloxane, (E) 0.1 to 3.0 parts by weight of nano catalyst, and (F) 0.1 to 3.0 parts by weight of additive. The thermal grease composition provided by the invention has good thermal conductivity and using weatherability, can effectively solve the technical difficulty that the thermal grease composition in the prior art is pulverized and crushed and the thermal conductivity is therefore reduced as the service time increases. The manufacturing process has simple, convenient and easy steps and the thermal grease composition is suitable for large-scale match production.

The invention provides a liquid thermosetting resin composition. The composition comprises the components in weight percentage: 30 to 80 percent of epoxide resin, 2 to 25 percent of firming agent, 20 to 80 percent of filling material, 0.001 to 5 percent of thixotropic agent, 0.001 to 5 percent of visbreaking dispersant, 0 to 5 percent of foam suppressor and a catalyst the weight of which is no more than 0.5 percent of the total weight of the epoxide resin and the firming agent; the components are mixed and evenly stirred; the liquid thermosetting resin composition has the advantages of good fluidity and metallic wettability, higher Tg, lower CTE and good self deaeration performance, and can overcome the defects of shrinkage in a hole, cracking in the hole, bubble in the hole and the connection of resins between holes. The invention also provides a method for manufacturing a printed circuit board by using the liquid thermosetting resin composition, which aims to improve the defects of the insufficient rubber filling after plate pressing and the cracking or the layering of resins after thermal shock and improve the credibility such as the heat reliability, etc. of the thick copper printed circuit board.

The invention discloses a II-type polymer cement waterproofing coating modified by nano materials, which consists of a liquid material component and a powder material component, wherein the liquid material component comprises the following ingredients by weight: 85-95 percent of acrylic ester latex, 0.5-2 percent of plasticizer, 0.2-0.4 percent of dispersant, 0.2-0.5 percent of silicone antifoam agent, 0.1-0.3 percent of preservative, 0.3-0.6 percent of active ingredient content of pre-dispersed nano silicon dioxide solution, 0.02-0.06 percent of active ingredient content of pre-dispersed nano alumina solution, and the balance of water. The mixture ratio of the liquid material component to the powder material component is 10:14-20 according to proportions by weight. The invention greatly improves the thixotropy of the coating, prevents coating elevation construction from sagging, reduces loss in coating construction, simultaneously enhances all properties of the coating such as water resistance, alkaline resistance and the like, and obtains obvious effects.

The invention discloses a heat-conductive silicone grease composition being high in heat conductivity and low in viscosity and freeness degree, and a preparation method of the silicone grease composition. The heat-conductive silicone grease composition includes organo-polysiloxane, heat conductive filler and other additives. By selecting the heat conductive fillers in multiple dimensions (one-dimension, two-dimension and three-dimension) and multiple scales (micron, submicron and nanometer) and in special ranges, synergistic effect among the multi-dimension and multi-scale fillers is achieved,thus achieving compact stack of the fillers in a local network structure. The heat-conductive silicone grease not only is improved in heat-conductivity but also has good flowability, low viscosity and low freeness degree.

A binder resin for a nonaqueous secondary battery electrode of the invention satisfies Is≧30 (Is indicates a sum of scattering intensities observed in a particle size range of from 1 to 100 nm) when a solution is formed by dissolving the binder resin in water at a concentration of 5% by mass and particle size distribution is measured by a dynamic light scattering method at 25° C. The binder resin contains a polymer (B) having a structural unit represented by the following Formula (11) and a specific structural unit. The binder resin also contains a polymer (α) having a specific structural unit and a structural unit represented by the following Formula (22), and / or a mixture of a polymer (β1) having a specific structural unit and a polymer (β2) having a structural unit represented by the following Formula (22).

The invention relates to the technical field of preparation of epoxy adhesives, particularly a high-strength high-toughness epoxy resin adhesive and a preparation method thereof. The epoxy resin adhesive comprises epoxy resin, diluter, coupling agent, fiber, filler, flame retardant, pigment, polyetheramine, fatty amine, aromatic amine curing agent, coupling agent and accelerator. Compared with the prior art, the high-strength high-toughness epoxy adhesive provided by the invention has the advantages of excellent adhesiveness, excellent thixotropy and excellent flowing resistance, and has high strength and favorable toughness after curing. The preparation method is simple to operate and suitable for industrial production. The epoxy adhesive can be used under harsh technological conditions, and has favorable effect on binding large-size components and devices.

The invention discloses a lost foam casting cast iron coating for preventing carbon defects, which comprises the following components by weight percent: 60.5%-64.5% of bauxite, 13.5-17.5% of kaolin, 3.5%-6.0% of talc powder, 1.7%-3.5% of attapulgite, 0.4%-0.8% of sodium lignosulphonate, 2.5%-6.0% of aluminum sulfate, 1.7%-3.5% of polyvinyl alcohol, 3.5%-5.0% of silica sol, 0.1%-0.2% of iron oxide powder and 0.01%-0.02% of n-octanol, and the sum of the components is 100%. The lost foam casting cast iron coating is prepared by respectively preparing water solution of the attapulgite, the polyvinyl alcohol and the aluminum sulfate, evenly mixing the bauxite, the kaolin, the talc powder and the iron oxide powder for preparing mixed powder material, mixing the water solution of the attapulgite, the polyvinyl alcohol and the aluminum sulfate, the silica sol and the refractory mixed powder material with the n-octanol, stirring and grinding. The coating has the advantages of good thixotropy, good coating property, high coating strength and good gas permeability; and the surface of a cast is smooth and has no wrinkles and other carbon defects.

The invention discloses copper welding paste for braze welding, a preparation method of the copper welding paste for braze welding and the application of the copper welding paste for braze welding. The copper welding paste for braze welding comprises 67wt%-92wt% of brazing filler metal, 8wt%-33wt% of pasty fluid and brazing flux of which the mass is 0-5% that of the brazing filler metal, wherein the brazing filler metal comprises Cu and / or one or more types of Cu alloy, the brazing flux comprises any one or more than two components of CaF2, KF, NaF, BaF2, sebacic acid, succinic acid, lauric acid and boric acid, and the pasty fluid comprises a solvent, a thickening agent, a rheological agent, an antifoaming agent and an activating agent. When the copper welding paste prepared through the method is applied before braze welding, the copper welding paste has good thixotropy, collapse resistance and fluidity; after braze welding, a part has high joint strength, a weld joint is plump and free of residues, and the part does not need cleaning; the copper welding paste can be widely applied to welding automobile pipe fittings, copper-based heat dissipation assemblies and stainless steel parts.

The invention discloses a weak-gel synthetic drilling fluid, which comprises 60-95 parts by volume of gas oil synthetic base liquid, 5-40 parts by volume of calcium chloride watery solution of which the mass fraction is 25-35%, as well as 1.0-3.5% of organic soil, 0.5-4.0% of primary emulsifier, 0.5-3.5% of auxiliary emulsifier, 0.5-3.5% of calcium oxide, 0.5-2.5% of wetting agent, 1.0-4.0% of filtrate reducer, 20-100% of weighting agent and 0.3-1.5% of optional activating agent according to a mass-volume ratio based on total volume fractions of the gas oil synthetic base liquid and the calcium chloride watery solution. The drilling fluid disclosed by the invention has the advantages as follows: (1) the synthetic drilling fluid has good thixotropy, and high low-shear rate viscosity, and (2) the plastic viscosity of the drilling liquid is smaller than that of the traditional drilling liquid.

The powerful adhesive includes neoprene, grafting monomer, thickener, dispersant, adhesion promoter, catalyst, antioxidant, solvent, stuffing, etc. The present invention also discloses the preparation process of the adhesive, and the preparation includes introducing grafting monomer to neoprene molecule chain to raise the adhesion strength, selecting proper adhesion promoting resin to increase the initial adhesion force, and adopting mixed solvent to form high adhering performance. The adhesive has high solid content and excellent environment protecting performance, and has also excellent antiageing performance, high resistance to heat, oil, chemical and corrosion, high weather resistance, good mildew-proof performance, antibiotic performance, etc. and may be used for adhering timber, concrete, rubber, metal, gypsum board, brick and other building material.

The invention relates to flame retardant high-heat-conductivity epoxy resin electronic adhesive glue, which is formed by mixing ingredients A with amine curing agents according to the weight ratio of 100:(5-12), wherein the ingredients A comprises the following ingredients in parts by weight: 50 to 60 parts of spherical alumina powder, 20 to 30 parts of flame retardant fillings, 10 to 20 parts of epoxy resin, 1.5 to 2.5 parts of reactive diluents, 2 to 3 parts of halogen-free liquid flame retardants, 2 to 3 parts of toughening agents, 0.2 to 0.8 parts of thixotropic agents and 0.1 to 0.5 parts of coupling agents. According to the adhesive glue provided by the invention, the adhesive glue filled by the spherical alumina has higher condensate heat conductivity when being compared with the adhesive glue filled by the non-spherical alumina, and the heat accumulation of heating devices can be fast dispersed.

The invention discloses a new unmanned express delivery conveying system and conveying method. Detailed plans are made from goods departure, to transportation paths, and finally to clients, so that the goods are safely, accurately and fast to be delivered to the clients. In addition the invention carries out further optimization on RF labels. The cost is reduced so as to make the system and conveying method of the invention to have stronger market competitiveness. The operation is simple and unattended. The unmanned express delivery conveying system runs 24 hours a day. RFID labels are automatically added to express delivery articles. It is helpful to automatic sorting. A large number of time and manpower are saved. After express items are in place, confirmation information is sent to recipients in real time, and the safety is improved. The unmanned express delivery conveying system and conveying method can be widely used in various communities where express delivery is frequently needed, and are safe and fast, low in cost and convenient in maintenance.

The invention relates to a high elastic corrosion resistant epoxy sealant and a preparation method thereof. The epoxy sealant provided by the invention comprises a component A and a component B in a weight ratio of 100:20-100:25. The epoxy sealant provided by the invention has advantages of high strength, high elasticity, low heat release, cracking resistance, good sealing performance and seawater corrosion resistance, is convenient for construction, and greatly improves sealing of key parts of ship stern tube.

The invention relates to wear-resistant epoxy glue and a preparation method thereof. The epoxy glue is prepared by mixing a component A and a component B based on a weight ratio of (100:11.1)-(100:13.3), wherein the component A comprises the following raw materials in parts by weight: 10-20 parts of liquid epoxy resin, 10-20 parts of bisphenol F epoxy resin with modified nano rubber particles, 2.5-5 parts of epoxy resin activity diluent, 0.5-1.0 part of coupling agent, 53-61 parts of aluminum oxide ceramic microsphere, 4-6 parts of white alundum powder, 3-5 parts of glass fiber powder, 0.5-1.2 parts of chopped nylon fiber and 1-2 parts of gas-phase silicon dioxide; and the component B comprises the following raw materials in percentage by weight: 55-65 parts of polyamide, 12-18 parts of isophorone diamine, 4-7.5 parts of AEPHP (N-Aminoethylpiperazine), 1-2 parts of solidification accelerating agent, 8-10 parts of kaolin, 3-6 parts of glass fiber powder and 3-5 parts of gas-phase silicon dioxide. The preparation method comprises the following steps: preparing the bisphenol F epoxy resin with modified nano rubber particles; respectively preparing the component A and the component B;and mixing the component A and the component B in proportion when the epoxy glue is used.

The invention discloses a development method of a novel water-based timber rubbling coloring agent, relates to a decorative coloring material, and especially discloses a coloring agent of products such as wooden interior and exterior decoration, floors and wood doors. The novel water-based timber rubbling coloring agent has diaphaneity and vividness and also has coloring, porefilling and primary coat sealing functions, the required different rare timber colors can be obtained by rubbing the coloring agent on the surface of a product through fabric, the application method is simple and convenient, the cost is low and reasonable, the water is utilized as a solvent, and the novel water-based timber rubbling coloring agent is green, innoxious and tasteless.

The invention discloses water montmorillonite nano composite heat insulating waterproof paint and a preparation method thereof. The water montmorillonite nano composite heat insulating waterproof paint comprises the following ingredients in percentage by mass: 30 to 35 percent of nano composite emulsion, 10 to 15 percent of polymer emulsion, 10 to 15 percent of rutile-type titanium pigment, 10 to15 percent of organic modified nano montmorillonite, 5 to 10 percent of nano oxide, 0.3 to 0.35 percent of pH adjusting agent, 0.50 to 0.65 percent of film-forming additive, 0.35 to 0.4 percent of elastic foam killer, 0.20 to 0.30 percent of wetting agent, 0.10 to 0.15 percent of dispersion agent, 0.50 to 0.65 percent of anti-freezing agent, 0.10 to 0.15 percent of sterilization antiseptic and 20to 25 percent of water. The water montmorillonite nano composite heat insulating waterproof paint not only has good compatibility, dispersion performance and good stability, but also has good water resistance, heat insulation, environmental protection, outdoor weather resistance and good adhesive attraction and has an antibacterial self-cleaning function.

The invention provides a fireflooding channeling sealing agent and its preparation method. Raw materials for preparing the fireflooding channeling sealing agent contain, by weight, 0.5-3% of a melamine substance, 0.2-1% of phenol, 2-8% of aldehyde, 0.5-2% of a pH regulator, 0.2-1.2% of a nano-alumina oleoresin liquid XZ-LY102, 10-20% of ultrafine silicon dioxide and the rest of water. Sealing rate of the fireflooding channeling sealing agent can reach 93%; temperature resistance reaches 300 DEG C; the highest salinity tolerance reaches 150,000 mg / L; expriation data can reach 6 months and above under the steam condition of 300 DEG C; viscosity of a profile control agent before gel forming is 150-1,500 mPa.S; sealing strength can reach 31 MPa / m; and gel forming time can be controlled within 12-36h. By the use of the fireflooding channeling sealing agent, deep profile control of an oil layer can be realized.

The invention relates to silver paste for a solar cell and a preparation method thereof. The silver paste comprises certain amounts of silver powder, turpentine and glass powder and fumed silica by mass percent, preferably nano methyl modified fumed silica. The silver paste further comprises a nonionic polymer surfactant which is a polyethoxyl / polypropoxy / polyethoxyl triblock copolymer. The silver paste which is prepared by mixing and stirring the above components according to a certain proportion and sequence and is used for the front of the solar cell has good thixotropy, improves the screen printing quality on the silicon wafer, improves the height-width ratio of the sintered screen printing silver wires and reduces the occupied sunlight area, thus improving the efficiency of the solarcell.

This invention discloses a method for preparing bentonite inorganic gel. The method comprises: mixing bentonite filter cake, sodium salt powder and urea powder to obtain a mixture, drying, pulverizing, and uniformly mixing with gelating agent to obtain bentonite inorganic gel. The sodium salt powder is one or more of sodium carbonate, sodium fluoride and sodium silicate. The addition amounts of sodium salt powder and urea powder are 2-10 wt. % and 0-20 wt. % of bentonite filter cake, respectively. The gelating agent is one or more of glues and cellulose substances, and the addition amount is 1-30 wt. % of the mixture. The method has such advantages as simple process, high efficiency, and high product performance, no toxicity and no harm, and is suitable for mass production.

The invention provides a method for preparing a paste soldering flux. The soldering flux comprises the following raw materials: resin, a solvent, an amine activating agent, a thixotropic agent, an organic acid activating agent and a corrosion inhibitor. The preparation method comprises the following steps of: a) stirring the resin and the solvent, heating until the resin is dissolved completely, cooling, adding the amine activating agent, and stirring until the amine activating agent is dissolved completely; b) adding the thixotropic agent, and emulsifying and dispersing by using emulsification equipment at constant temperature, so that the thixotropic agent forms a thixotropic gel network structure; c) adding the organic acid activating agent, reacting with the amine activating agent to form a salt compound, and adding the corrosion inhibitor and stirring to dissolve the salt compound; and d) stirring and cooling slowly to room temperature to obtain the paste soldering flux. The prepared paste soldering flux is mainly applied to soldering paste formed by stirring and mixing the paste soldering flux and superfine solder powder under vacuum, and has high heat collapse resistance, and high viscosity stability in the processes of storage and printing to avoid the 'post-thickening' phenomenon.

The invention discloses dielectric paste for a metal aluminum substrate thick film circuit and a preparation method thereof. The invention aims to prepare the dielectric paste matched with a metal aluminum substrate. The dielectric paste is characterized in that SiO2, Na2O, B2O3, K2O, BaO, CaO, Co2O3, TiO2, P2O5, V2O5, Sb2O3 and Cr2O3 are combined to prepare microcrystalline glass powder; and the microcrystalline glass powder and an organic binder which consists of terpinol, butyl carbitol, butyl carbitol acetate, tirbutyl citrate, 1,4-butyrolactone, nitroncellulose, ethyecellulose, hydrogenated castor oil and lecithin are put in a vessel for stirring and rolling by a three-roll roller mill in a weight ratio of the microcrystalline glass powder to the organic binder of 70-90 parts: 30-10 parts so as to prepare the finished product dielectric paste. The dielectric paste is mainly used as the dielectric paste of the thick film circuit formed by being printed on the metal aluminum substrate.

The invention relates to a heat conductive phase-change material which consists of the following components in percentage by weight: 75-90% of heat conductive filler, 2-8% of low-melting-point solid resin, 5-15% of liquid resin, 0.01-1% of an antioxidant and 0.02-2% of a coupling agent, and the phase-change material is prepared through a production method of mixing raw materials, mixing the heat conductive filler, pressing and forming, and cooling. The heat conductive phase-change material, which is prepared by mixing the heat conductive filler, the low-melting-point solid resin, the liquid resin, the antioxidant and the coupling agent, disclosed by the invention has the advantages that the phase-change material is in a shape of flaky solid at room temperature, so that the material is convenient in using and operation and can be directly attached on the surface of a heat-radiating component; when the component runs to the working temperature of the heat conductive phase-change material, phase change occurs and the material becomes soft, so as to wet the surface of the component to a great extent, and contact thermal resistance is reduced to the lowest so as to guarantee a heat conductive interstitial property better than that of heat conductive grease or a graphite flake; in addition, with excellent thixotropy, the material, when being used in a vertical direction, is protected away from circumstance of overflow or flowing.