116 results about "Chromate and dichromate" patented technology

The disclosure relates to a method of producing a multi-metal catalyst film and of producing a reactor system for catalytic removal of a wide variety of contaminants (for example, nitrate, nitrite, perchlorate, chlorate, chromate, selenate, chlorophenols, 2,4-D, dicamba, atrazine, trichloroacetic acid, bromochloroiodomethane, NDMA, TCE, TCA, chloroform, freons, RDX, HMX, TNT, PFOA, and PFOS) from water and wastewater. The disclosure also relates to a method of using the multi-metal catalyst for the removal of such contaminants and a system comprising the multi-metal catalyst film for removing such contaminants.

The invention belongs to the field of catalysts for oxygen production through seawater electrolysis, and particularly discloses a chromium-doped ferronickel sulfide nanorod array material, a preparation method thereof and application of the chromium-doped ferronickel sulfide nanorod array material to oxygen evolution through seawater electrolysis. The material is a chromium-doped ferronickel sulfide grown in situ on a foamed ferronickel substrate, has components of NiFe, Ni3S2 and (Fe, Ni) 3S4, and is of a nanorod array structure. The preparation method comprises the following steps: putting the cleaned foam ferronickel into a solution containing a sulfur source and chromate, and obtaining the chromium-doped ferronickel sulfide nanorod array material by utilizing a hydrothermal method. As an alkaline water and seawater oxidation electrode, the composite material shows extremely excellent catalytic activity and stability, and has potential application value in the aspect of developing a transition metal OER catalyst for electrolyzing seawater to evolve oxygen.

The invention discloses a heat storage unit and an assembling method and application thereof. The heat storage unit comprises a metal heat storage shell and a phase change layer, a heat storage space in the metal heat storage shell is filled with the phase change layer, and a phase change material of the phase change layer comprises the following components: 85.0 wt.%-95.0 wt.% of a phase change base material, 1.0 wt.%-3.0 wt.% of a nucleating agent, 2.0 wt.%-4.0 wt.% of a thickening agent and 0.5 wt.%-2.0 wt.% of a corrosion inhibitor; the phase-change base material comprises one of saturated fatty acid, an alcohol compound or an inorganic phase-change base material; the corrosion inhibitor comprises at least one of a nitrogen-containing heterocyclic compound, an oxygen-containing heterocyclic compound, molybdate, chromate and tungstate. A phase change base material and a corrosion inhibitor are selected for combined use, the corrosion inhibitor dissociates and forms substances with negative charges such as BTA <->, MnO4 < 2-> and CrO4 < 2->, a metal shell is in contact with the phase change material to lose electrons to form metal ions with positive charges, and the metal ions are combined with the substances with negative charges such as BTA <->, MnO4 < 2-> and CrO4 < 2-> to generate a compact long-chain complex. Further contact between other corrosion ions and metal is inhibited, so that the purpose of corrosion prevention is achieved.

The invention discloses a modified polyaniline synergistic flaky zinc-aluminum waterborne epoxy anticorrosive coating and a preparation method thereof. The anticorrosive coating comprises a component A and a component B in a mass ratio of (4-5): 1, the component A is prepared from the following components in parts by weight: 8 to 16 parts of waterborne epoxy resin, 55 to 75 parts of zinc powder, 5 to 10 parts of flaky zinc-aluminum powder, 0.3 to 0.6 part of a dispersing agent, 0.5 to 1 part of an anti-settling agent, 0.1 to 0.3 part of dodecylbenzene sulfonic acid doped polyaniline, 1 to 2 parts of an adhesion promoter and 6 to 10 parts of a first solvent; and the component B comprises the following components in parts by weight: 3-7 parts of a water-based amine curing agent, 1-2 parts of an anti-flash-rust auxiliary agent, 5-10 parts of a second solvent and 2-5 parts of deionized water. The obtained coating is compact, excellent in corrosion resistance, good in adhesive force, few in organic volatile matter, easy to prepare, convenient to operate and completely free of chromate, and the corrosion resistance far beyond that of conventional paint is achieved.

The invention belongs to the technical field of precision part machining, and discloses a precision part corrosion-resistant coating process, electrochemical treatment is chromic acid treatment, coating materials comprise epoxy resin coating, polyurethane coating and polytetrafluoroethylene coating, and a spraying technology comprises electrostatic spraying, air spraying and airless spraying. Hydrochloric acid is used for removing oxides on the surface of steel, phosphoric acid is used for removing rust on the surface of metal, through cooperation of acid pickling, passivation and electroplating, acid pickling and passivation can remove the surface oxides, the hardness and friction resistance of the surface of the metal can be improved, and electroplating can improve the surface hardness of parts, improve abrasion resistance and prevent corrosion; a protective film is formed through passivation treatment, further oxidation is prevented, chromate passivation soaking time is 10-30 minutes, phosphate passivation soaking time is 5-15 minutes, nitric acid passivation soaking time is 5-10 minutes, and durability, corrosion resistance and surface hardness of the precision part are improved.

The invention relates to the technical field of chemical mechanical polishing solutions, in particular to a chemical mechanical polishing solution for silicon carbide and a preparation method thereof, the polishing solution comprises a catalyst, abrasive particles, a dispersing agent, an oxidizing agent, a surfactant, an acid-base regulator and deionized water; the catalyst is nano platinum particles; the abrasive particles are aluminum oxide; the dispersing agent is at least one of sodium polyacrylate, sodium hexametaphosphate, hexadecyl trimethyl ammonium bromide and the like. The oxidizing agent is at least one of permanganate, pypocholoride, dichromate and the like; the surfactant is at least one of sodium dodecyl benzene sulfonate, organic bentonite and the like; the pH regulator is at least one of phosphoric acid, nitric acid, oxalic acid and citric acid. The polishing solution can effectively improve the removal rate of silicon carbide, and meanwhile, a polished silicon carbide wafer is high in flatness and free of scratches.

Provided is a tin-plated steel sheet for containers, said steel sheet having a zirconium-containing coating layer, without having to undergo conventional chromate treatment. The tin-plated steel sheet has further excellent yellowing resistance. A tin-plated steel sheet having: a steel sheet; a tin plating layer on at least one surface of the steel sheet; and a coating layer that is positioned on the tin plating layer and contains zirconium oxide and tin sulfide, the amount of tin plating layer deposited in the coating layer being 0.1 g / m2 to 15 g / m2 in terms of the amount of metal Sn, the amount of zirconium oxide deposited in the coating layer being 0.2 mg / m2 to 50 mg / m2 in terms of the amount of metal Zr, and the amount of tin sulfide deposited in the coating layer being 0.1 mg / m2 to 5 mg / m2 in terms of the amount of sulfur.

The present invention relates to a high-entropy rare earth chromate high-temperature negative temperature coefficient thermistor material, belonging to the field of semiconductor sensors, and aims to solve the existing perovskite structure high-temperature NTC material. Under high temperature environment, the Cr element in the system will volatilize in the form of gaseous CrO3, showing poor high-temperature aging stability. The high-temperature negative temperature coefficient thermistor material uses lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide and chromium trioxide as raw materials, and undergoes wet three-dimensional vibration ball milling, powder calcination, cold isostatic pressing, and high-temperature sintering to obtain a perovskite structure (La 0.2 Nd 0.2 Sm 0.2 Eu 0.2 G 0.2 )CrO3 thermosensitive material. The electrical performance parameters of this series of materials are: B 0℃ / 1300℃ =2044±1.42%K,ρ 1300℃ =1.45×10 3 ±1.73%Ω·cm. The high-entropy rare earth chromate high-temperature negative temperature coefficient thermistor (La 0.2 Nd 0.2 Sm 0.2 Eu 0.2 G 0.2 )CrO3 has excellent negative temperature coefficient characteristics in the temperature range of 0~1300℃, and shows good high temperature aging stability at high temperatures (the resistance drift rate is only 4.35% after aging for 500 hours at 1300℃).

A method for manufacturing a cover member for electronic devices according to certain embodiments of the present disclosure may comprise: a step for forming a magnesium plate; a step for performing primary CNC processing on the magnesium plate using a predetermined cutting oil; a step for performing a primary pretreatment on the magnesium plate using chromate or micro arc oxidation (MAO); a step for performing a primary surface-treatment on the magnesium plate by bake-coating or electrodeposition coating; a step for performing secondary CNC processing on a first region of the magnesium plate using an alcohol-containing cutting oil; a washing and drying step; a step for performing a secondary pretreatment for preventing oxidation on the first region; and a step for performing a secondary surface-treatment on the first region by bake-coating or electrodeposition coating.

The invention discloses an electrolytic copper foil surface roughening method. The method comprises the following steps: performing degreasing, water washing and acid pickling activation pretreatment on an electrolytic copper foil to remove oil stains, impurities and an oxide layer on the surface; primary coarsening, curing treatment, secondary coarsening and post-treatment are sequentially carried out, and in the primary coarsening process, electrolyte containing specific components is utilized, and electrolysis is carried out under the specified current density, temperature and time; a specific curing liquid is adopted for curing treatment, and relevant parameters are controlled; an electrolyte containing lanthanum sulfate and other components is used for secondary coarsening; the post-treatment comprises water washing, repeated coarsening, chromate passivation and hot air drying. According to the electrolytic copper foil treated through the method, the surface roughness Rz is smaller than or equal to 2.5 micrometers, the (220) crystal face proportion exceeds 80%, the peeling strength with a substrate reaches 1.2 N / mm or above, the application requirements of high-speed and high-frequency PCBs and high-performance lithium ion batteries can be effectively met, and the product performance and quality are improved.

The present application relates to the technical field of insulating coating material, and particularly relates to a colored insulating coating composition of a lithium ion battery positive electrode sheet. The colored insulating coating composition of the lithium ion battery positive electrode sheet comprises the following components: a filler 50% to 98%, a pigment 1% to 80%, a binder 1% to 10% and a solvent 10% to 50%; wherein the pigment is selected from any one of metal oxides, chromates, carbonates, sulfates and sulfides. The colored insulating coating composition provided by the present application has good insulating performance, stable electrochemical properties and stable chemical properties. The present application further provides a lithium ion battery positive electrode sheet, which comprises a current collector, a positive electrode active material layer and a colored insulating coating; the colored insulating coating is coated on the surface of the current collector; the positive electrode active material layer is coated on the surface of the current collector and is arranged on one side of the colored insulating coating; the colored insulating coating is spliced and connected with the positive electrode active material layer; wherein the colored insulating coating is formed by the colored insulating coating composition as described above.

The invention discloses a method for simulating phosphorus and chromium migration during farmland irrigation with acid mine wastewater, which comprises the following steps: mixing a plant-derived organic material with deionized water to obtain a soluble organic matter; h2O2 oxidizes Fe < 2 + > to prepare pure Schwertmannite, and the pure Schwertmannite is placed in a phosphate solution to obtain phosphorus-loaded Schwertmannite; mixing the phosphorus-loaded Schwertmannite and the soluble organic matter with a chromate solution, carrying out oscillation adsorption, carrying out solid-liquid separation after adsorption, carrying out CrO and POconcentration change test on filtrate, and carrying out mineral characterization on separated solids; a three-dimensional fluorescence spectrum is adopted to track composition conversion of the soluble organic matter in the reaction process; and analyzing the component change of the supernate before and after the reaction by adopting Fourier transform ion cyclotron resonance mass spectrometry. The influence mechanism of DOM on phosphorus and chromium fate in mineral / water interface molecular fractionation is disclosed from the molecular level, and a scientific basis is provided for collaborative migration risk assessment of phosphorus and heavy metal in acid mine wastewater irrigation area farmland.

The present invention discloses a multi-code parallel circuit board hole anti-passivation process, which comprises the following steps: step S1, feeding; step S2, overflow water washing; step S3, drying treatment; step S4, collecting the material. The present invention discloses a multi-code parallel circuit board hole anti-passivation process, which is simple and easy to understand, has a long board placement time, does not contain halides and chromates, is safe and environmentally friendly to use, has a better passivation effect, has a low production cost, does not require special equipment, has high production efficiency, can simultaneously achieve higher economic benefits, social benefits and ecological benefits, and has a high value of promotion and use.

A stainless steel pouch film for a secondary battery, comprising: a stainless steel layer, any one of a first surface and a second surface being treated with chromate and corona; an outer resin layer formed on the first surface of the stainless steel layer; and an inner resin layer formed on the second surface of the stainless steel layer, wherein the outer resin layer comprises polyethylene terephthalate.

A method for determining the presence of chromium-6 (Cr-6) in a solid sample is described, comprising the steps of contacting the solid sample with a destruction liquid under conditions in which the Cr-6 of the solid sample dissolves in the destruction liquid as a chromate, providing a test solution; subjecting the test solution obtained in step (1) to a specific Cr-6 detection reaction, under conditions in which the presence of Cr-6 is detected; and detecting whether the specific Cr-6 reaction occurred in step (2); wherein the destruction liquid comprises an oxidant, which has a standard electrode potential E0 higher than the chromate.

Provided is a tin-plated steel sheet which is more excellent in yellowing resistance in a steel sheet for containers having a film layer containing zirconium without being subjected to a conventional chromate treatment. A tin-plated steel sheet is adopted which has a steel sheet, a tin plating layer located on at least one surface of the steel sheet, and a film layer located on the tin plating layer and containing zirconium oxide and tin sulfide, in which an adhesion amount of the tin-based plating layer is 0.1 g / m2 or more and 15 g / m2 or less in terms of the amount of metal Sn, an adhesion amount of the zirconium oxide in the film layer is 0.2 mg / m2 or more and 50 mg / m2 or less in terms of the amount of metal Zr, and an adhesion amount of the tin sulfide is 0.1 mg / m2 or more and 5 mg / m2 or less in terms of the amount of sulfur.

The present invention relates to systems and methods for catalytic removal of oxidized contaminants (for example, nitrite, chromate, chlorate, trichloroethene, CFC-11, 4-nonylphenol, RDX, and perfluorooctanoate) from water and wastewater. In some aspects, the catalytic method of removing oxidized contaminants comprises using precious metal nanoparticles as catalysts to reduce the oxidized contaminants.

The invention discloses an organic inhibitor for galena and application of the organic inhibitor. The inhibitor is 3-mercapto-1 sodium propane sulfonate (MPS). Aiming at the characteristics of close copper and lead symbiosis, high iron and zinc content and fine disseminated particle size of raw ore, the method adopts the technological process of'copper and lead partial bulk flotation tailing discarding-bulk concentrate regrinding-copper and lead separation flotation ', and comprises the following steps: firstly, in a bulk flotation section, utilizing a zinc sulfate and sodium sulfite combined reagent to efficiently inhibit sphalerite and pyrite under a weakly alkaline condition; a large number of gangue and zinc-sulfur minerals are thrown away in advance; the method comprises the following steps of: carrying out superfine regrinding dissociation on obtained bulk concentrate, then carrying out separation operation, and in a copper-lead separation section, replacing traditional dichromate with 3-mercapto-1 sodium propane sulfonate (MPS), carrying out a closed-loop process of one-roughing, three-refining and three-sweeping, and supplementing an inhibitor in fine selection operation, so that efficient inhibition of galena and preferable flotation of chalcopyrite are realized. The technological process is rigorous in design, the reagent system is green and environmentally friendly, and the resource recovery rate of the low-grade complex ore is remarkably increased.

To provide a coated steel sheet that is excellent in corrosion resistance even when not containing a chromate compound and is excellent in coating film adhesion and corrosion resistance at the cut end. 【Means for Solving the Problem】To achieve the above object, the present invention provides a coated steel sheet comprising a zinc-based plated steel sheet, a chemical conversion coating film, and a coating film, wherein the coating film contains a thermosetting resin obtained by thermosetting a polyamide resin (A) having a dimer structure derived from at least one of dimer acid and dimer diamine and an epoxy resin (B), the weight average molecular weight of the polyamide resin (A) is 3000 to 20000, the glass transition temperature (Tg) is 5 to 120 ° C, the acid value is 5 to 15 (mgKOH / g), the amine value (mgKOH / g) is 0.2 to 0.7, the epoxy equivalent of the epoxy resin (B) is 130 to 450, the content ratio of the polyamide resin (A) and the epoxy resin (B) is 70:30 to 95:5, the glass transition temperature (Tg) of the coating film is 25 to 90 ° C, and the dynamic storage elastic modulus at the glass transition temperature + 100 ° C (Tg + 100 ° C) is greater than 1 × 10 7 Pa, and less than 2 × 10 8 Pa. It is characterized by this.

The application discloses a kind of anti-chromium-poisoning core-shell structure solid oxide fuel cell cathode and its preparation method, the anti-chromium-poisoning core-shell structure solid oxide fuel cell cathode is formed with screen printing LSCF as core layer, with metal-doped cerium-based oxide as shell layer;The shell layer is uniformly coated on the surface of core layer;The cathode is loaded on the surface of SOFC half cell with GDC barrier layer, the cathode has the shell layer of physical barrier effect, can block gaseous Cr and LSCF active site contact, no chromate is generated on the surface of cathode after long-term operation, effectively solve the problem of cathode poisoning attenuation.

The present invention provides a continuous flow process for preparing nitroacetic acid ester compounds, belonging to the field of chemical pharmaceutical preparation. This process avoids the use of dichromate, thus preventing heavy metal pollution; avoids the use of nitric acid, thus avoiding the highly dangerous nitration reaction; and implements automated control, reducing the risks and costs of manual operation, thereby achieving safe, environmentally friendly, and efficient green chemical production.

The invention relates to the technical field of railway steel production, and particularly discloses an environment-friendly zinc-aluminum-magnesium coated steel rail and a preparation method thereof.The preparation method comprises the steps that the steel rail is pretreated to obtain a clean steel rail; alloy coating spraying is conducted on the clean steel rail, and a steel rail intermediate is obtained; performing surface hole sealing treatment on the steel rail intermediate; the chromium-free passivation solution comprises water-based acrylic resin, tannic acid, an organic silane coupling agent, silica sol, fluotitanic acid, polyethyleneimine, ethyl alcohol and deionized water. By adopting a chromium-free passivation technology, the technical problems that a chromate passivation technology is high in biotoxicity and does not meet the requirements of modern environmental protection development are effectively solved, and by adopting the water-based acrylic resin, the obtained coated steel rail has excellent corrosion resistance and can form a stable protective film on the metal surface; and the coating has the characteristics of good environmental protection property and convenience in construction, and can be well matched with various metal substrates, so that the service life of a metal workpiece is effectively prolonged.

The present application belongs to the technical field of electrolytic copper foil, and provides a chromium-free anti-oxidation method for electrolytic copper foil, which solves the problem of copper foil oxidation under chromium-free condition. The electrolytic copper foil is sequentially subjected to pickling, roughening I, roughening II, electroplating, passivation, silane coupling and drying to complete the treatment of the electrolytic copper foil. In the process of treating the copper foil, a Ni-Cu-Sn alloy layer is deposited on the surface of the copper foil through a specific composition of electroplating solution, so as to achieve the purpose of preliminary protection. Then, passivation is carried out in a passivation solution, and the passivation solution can effectively form an organic adsorption film to inhibit the oxidation of the electrolytic copper foil. On the basis of abandoning the addition of chromate, the present application can still well improve the anti-oxidation property of the electrolytic copper foil, and there is no oxidation discoloration under high-temperature and high-humidity conditions, and the electrolytic copper foil is resistant to chemical reagents, and the tensile strength under high temperature reaches 406 MPa, and has excellent mechanical properties.

The present invention discloses a method and system for measuring the concentration of divalent iron in the electrolyte of a Fe / Cr flow battery. The measurement method includes: mixing the positive electrolyte and the negative electrolyte in equal volume to obtain a mixed electrolyte; mixing the mixed electrolyte with an acid and an excessive amount of soluble dichromate so that the divalent iron in the mixed electrolyte is fully oxidized to trivalent iron to obtain an acidic test solution; introducing a pair of electrolysis electrodes and a pair of measurement electrodes into the acidic test solution, performing direct current constant current electrolysis on the acidic test solution through the electrolysis electrodes to reduce the trivalent iron in the acidic test solution, and simultaneously detecting the potential between the measurement electrodes by a potentiometer and recording the electrolysis duration required when the potential suddenly drops; obtaining the concentration of divalent iron in the electrolyte of the Fe / Cr flow battery according to the added amount of the soluble dichromate, the current magnitude of the constant current electrolysis, and the electrolysis duration. This measurement method has the advantages of accurate measurement results, high reliability, etc.

The invention relates to the technical field of hazardous waste disposal and utilization, in particular to a technological method for co-disposal of chromic anhydride waste and waste zinc phosphide, which comprises the following steps: dissolving chromic anhydride waste in a dissolving tank according to a certain solid-to-liquid ratio, and hydrolyzing chromic anhydride to generate chromic acid; the method comprises the following steps: adding a certain proportion of an inorganic acid solution into a chromic acid solution, and combining chromate ions with hydrogen ions to generate dichromate ions under an acidic condition; transferring the solution into a closed first-stage reactor, and slowly stirring; according to the method, firstly, the method is suitable for chromic anhydride waste and zinc phosphide waste, waste chromate, dichromate waste and aluminum phosphide waste can be used, harmless treatment of the hazardous waste can be completed, secondly, reagents used in the treatment process only need phosphoric acid, hydrogen peroxide and sodium hydroxide, ferrous sulfate is not used as a reducing agent, and the method is environmentally friendly. The production of a large amount of iron mud is avoided, and finally, the produced secondary waste can be recycled, so that the aim of turning waste into wealth is fulfilled.

A method of surface treatments that provide additional characteristics to the surfaces of galvanized steel materials is provided. A chromate-free coating material is applied after texturing on the surface of the galvanizing steel material and obtaining the roughness values. The resulting galvanized steel material provides a stainless-steel alternative sheet materials with high corrosion resistance and anti-fingerprint characteristics.

The invention discloses an efficient flotation inhibitor for galena and pyrite separation and application of the efficient flotation inhibitor. The inhibitor adopts a ternary compound system of modified lignosulfonate, an organic phosphate corrosion inhibitor and an organic reducing agent, and all the components have a synergistic effect. And the used components are low-toxicity or non-toxic organic compounds and do not contain extremely toxic substances such as cyanide and dichromate, so that the alkaline tailing pollution of a high-alkali lime method is avoided, and the green mineral separation requirement is met. During application, efficient separation can be realized under a weak base condition, the pH of ore pulp does not need to be increased to 11 or above, lime consumption is greatly reduced, corrosion and abrasion of equipment are reduced, and meanwhile, the over-inhibition risk of galena is reduced. The dosage of a roughing inhibitor is small, and the total dosage is low due to subsection decrement addition during concentration. And the N, N-diethyldithiocarbamate is adopted as the collecting agent, the agent system is simple, and industrial implementation is easy. The inhibitor still has a good inhibition effect on pyrite activated by copper ions, overcomes the defect of poor adaptability of a traditional high-alkali method, and has strong adaptability to ores with different properties.

The utility model discloses an adsorption / desorption integrated device for treating chromium-containing waste liquid, and relates to a device for treating chromium-containing waste liquid. The utility model aims to solve the technical problems that the existing device for treating the chromium-containing waste liquid is relatively complicated in structure and relatively large in occupied area. The device consists of a tank body, a motor, an upper filter plate, a lower filter plate, a spoiler, a window, a stirring rod and a stirring blade, and the chromium-containing waste liquid is treated by utilizing a targeted adsorption technology, so that the treatment cost of the traditional physicochemical technology is reduced. After adsorption, the hexavalent chromium can be enriched and concentrated through regeneration of a desorption solution, traditional landfill treatment of chromium-containing waste liquid-chromium sludge is transformed into high value of chromium-containing waste liquid-chromate product resources, and an ecological closed loop is carried out. In the whole process, the adsorption and desorption processes are carried out in an integrated device, so that the occupied area of the device is reduced.

The present invention discloses a corrosion-resistant preparation process for stainless steel under extreme working conditions, and relates to the technical field of stainless steel surface treatment. The present invention adopts coating protection technology to achieve corrosion-resistant protection of stainless steel under extreme working conditions. The coating in the present invention includes 10~30wt% aluminum dihydrogen phosphate, 5~10wt% silica sol, 5~10wt% aluminum sol, 1~5wt% molybdenum oxide, 0.1~1.0wt% carboxymethyl cellulose, 0.1~1.0wt% polyvinyl alcohol, and also involves cobalt tungstate nanofibers. The present invention forms complementary advantages through reasonable design of the coating formula content and the components, forms a good gradation between the components, improves the density of the coating and the connectivity between the components and the components, and between the components and stainless steel, improves the corrosion resistance of the coating, and is different from traditional coatings, does not contain Cr such as chromic anhydride or chromate. 6+ Ingredients, harmless to human body and environment, safe and environmentally friendly.

This surface-treated copper foil, comprising a heat-resistant treatment layer and a chromate treatment layer but without a roughening treatment layer, exhibits excellent heat resistance and corrosion resistance. Furthermore, because the amount of nickel and chromium adhering to the treated surface is small, there is less conductor loss due to dissimilar metals, and because of its low roughness and lack of conductor loss due to roughening particles, it is suitable for copper-clad laminates used in high-speed transmission printed circuit boards. [Solution] The arithmetic mean height Sa of the untreated copper foil surface is less than 0.27 μm, the unfolded interface area ratio Sdr is less than 6%, the surface area ratio calculated from Sdr is A, and the two-dimensional area of ​​the surface-treated copper foil surface is 1 m². 2 When the amount of nickel deposited per unit area (mg) is B, the surface area is 1 m². 2 The amount of nickel deposited per unit [B / A] is 5 mg to 31 mg, and the two-dimensional area of ​​the surface-treated copper foil surface is 1 m². 2 When the amount of chromium deposited per unit area (mg) is C, the surface area is 1 m². 2 Surface-treated copper foil with a chromium content per unit area [C / A] of 1 mg to 4 mg.