Showing papers on "Electroless nickel plating published in 2010"
TL;DR: In this paper, a phytic acid conversion film with especial functional groups was proposed as the pretreatment layer between Ni-P coating and AZ91D magnesium alloy substrate, to replace the traditional pretreatment.
49 citations
TL;DR: In this paper, a new activation process was developed for electroless plating to prepare wood-based EMI shielding material and an Ni-P coating was deposited on the wood veneer.
40 citations
TL;DR: In this paper, a simple electroless Ni-P plating process for preparing a conductive wood veneer has been developed, where activation was combined with electroless deposition in the plating solution.
Abstract: A new, simple electroless Ni–P plating process for preparing a conductive wood veneer has been developed. In this process, the activation was combined with electroless deposition in the plating solution. This provides a simple, environmentally friendly method, by which a Ni–P layer was successfully deposited on the surface of Manchurian ash veneer. It was observed by scanning electron microscopy that the deposited layer was uniform, compact and continuous. Results from energy-dispersive spectroscopy showed that a low-phosphorus layer was obtained, which contained about 4 wt.% phosphorus and 96 wt.% nickel. X-ray diffraction analysis indicated that the coating was crystalline. It is considered that the crystalline structure is related to the low-phosphorus content of the layer. Veneers plated with the crystalline Ni–P coating had good electrical conductivity, with a surface resistivity less than 200 mΩ/cm 2 and a firm adhesion of the Ni–P coating to the wood.
38 citations
TL;DR: The direct patterning of metallic layers onto insulating substrates indicates a great potential for fabricating micro/nano devices and shows good adhesion with glass and plastic substrates.
Abstract: We demonstrate a simple route to depositing nickel layer patterns using photocross-linked polymer thin films containing palladium catalysts, which can be used as adhesive interlayers for fabrication of nickel patterns on glass and plastic substrates. Electroless nickel patterns can be obtained in three steps: (i) the pattern formation of partially quaterized poly(vinyl pyridine) by UV irradiation, (ii) the formation of macromolecular metal complex with palladium, and (iii) the nickel metallization using electroless plating bath. Metallization is site-selective and allows for a high resolution. And the resulting nickel layered structure shows good adhesion with glass and plastic substrates. The direct patterning of metallic layers onto insulating substrates indicates a great potential for fabricating micro/nano devices.
36 citations
TL;DR: In this paper, the adsorption of Ag nanoparticles onto the poly(ethylene terephthalate) (PET) was promoted by conditioning the substrate with 3-aminopropyltrimethoxysilane and 3-mercaptoprocessyl- triethoxylynne.
Abstract: Silver nanoparticle catalyst was prepared to replace Pd catalyst for electroless Ni plating. The adsorption of Ag nanoparticle onto the poly(ethylene terephthalate) (PET) was promoted by conditioning the substrate with 3-aminopropyltrimethoxysilane and 3-mercaptopropyl- triethoxysilane. Electroless Ni deposition was started at the PET substrates catalyzed with Ag nanoparticle linking to the substrate via Ag–S bond. The composition and topography of nickel plating PET films were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and energy dispersive X-ray (EDX) analysis, respectively. Peel adhesion strength, more than 50 N/cm, was achieved for planting nickel layer to the Ag activated PET substrate; however, a relative low value as 10.2 N/cm was obtained for the sample with Pd catalyst by the same measurement. Silver catalyst together with silane modification has the significant merits for electroless deposition of Ni on PET film.
30 citations
TL;DR: In this paper, a process of blackening of electroless nickel coating is investigated to produce ultra black coating on titanium alloys with higher optical properties, which is extremely suitable for spacecraft thermal control applications.
Abstract: A process of blackening of electroless nickel coating is investigated to produce ultra black coating on titanium alloys with higher optical properties. Process optimization was carried out by investigating the influence of various operating conditions, namely, processing time of etching solutions, thickness of electroless nickel deposit, temperature of blackening solutions, and pH of electroless nickel solution on the physico-optical properties of the black coating. It was observed that an optimum thickness of 35 + 5 μm of electroless nickel is required to achieve the ultra high optical properties after blackening. Energy dispersive X-ray spectroscopy studies suggested that films containing ~7% phosphorous are good for further blackening. Scanning electron and optical microscopic studies confirmed that the surface morphology played the major role to get the ultra high optical properties. The environmental tests, namely, humidity, corrosion resistance, thermal cycling, thermo vacuum performance, and thermal stability tests were used to evaluate the space worthiness of the coating. Optical properties of the coating were measured before and after each environmental test to ascertain its stability. The blackened electroless nickel provides higher optical properties in the order of ~0.85; this coating has good adhesion, uniformity, and stability in adverse space conditions. Hence, these coatings were extremely suitable for spacecraft thermal control applications.
28 citations
TL;DR: In this article, the morphology, component, chemical composition and structure of the pretreatment layers and electroless nickel coating were analyzed using scanning electronic microscopy, energy dispersive spectroscopy, X-ray photoelectron spectrography and Xray diffraction spectrograms.
Abstract: To improve the corrosion resistance of ZM6 (Mg–2.6Nd–0.6Zn–0.8Zr) magnesium alloy, electroless nickel plating on ZM6 alloy with a new pretreatment process and nickel carbonate bath was investigated in this paper. The morphology, component, chemical composition and structure of the pretreatment layers and electroless nickel coating were analyzed using scanning electronic microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction spectroscopy. The adhesion and corrosion resistance of the Ni–P coating were evaluated by means of thermal shock, potentiodynamic polarization, and salt spray test. The results showed that a compact zinc immersion layer was formed on the surface of the ZM6 alloy in a new zinc dipping solution. The subsequent amorphous electroless nickel coating was uniform, in which the content of P was 9.7 wt.%. Its thickness reached about 62 μm at 2 h deposition. Compared with the bare substrate, the corrosion potential of the coated alloy shifted by 1075 mV positively and the corrosion current density decreased two orders of magnitude in 3.5 wt.% NaCl solution. The salt spray test time of Ni–P coating was 158 h. These results suggest that the electroless nickel plating procedure developed in the study is available for ZM6 alloy and the Ni–P coating obtained with good adhesion could protect the substrate effectively.
26 citations
TL;DR: In this article, the physical characteristics and microstructure of the fluoride film formed during activation were investigated using SEM, XPS and SAM, and its stability in electroless nickel (EN) bath was analyzed.
24 citations
TL;DR: In this article, a selective electroless nickel-phosphorus (NiP) deposition without the activation step from an alkaline bath containing sodium hypophosphite as a reducing agent and ammonia for pH control is presented.
Abstract: Electroless nickel plating is a very promising process for metallization of silicon solar cells. It can be used to form a seed layer for an electrolytic deposition of copper or silver because it ensures the required adherence, a low contact resistance, and prevent copper from diffusing into the silicon. The nickel plating technique developed in this work consists of a selective electroless nickel-phosphorus (NiP) deposition without the activation step from an alkaline bath containing sodium hypophosphite as a reducing agent and ammonia for pH control. Experimental results of the deposit properties are presented. Thin NiP layers of about 0.1 μm on silicon were annealed under different conditions. Rutherford backscattering spectrometry, glancing incidence X-ray diffraction, and scanning electron microscopy were used to obtain information on silicide formation vs temperature. These results were correlated with contact resistivity measurements by the transmission line model. A typical contact resistivity of 10 -4 Ω cm 2 has been obtained.
21 citations
22 Nov 2010
TL;DR: In this paper, a 1.7 µm thick nickel layer is deposited on top of 600 nm thick printed and sintered silver nanoparticles using Kapton polyimide as substrate.
Abstract: The nanoporous nature of the inkjet printed silver nanoparticles entail low hardness and surface effective contact area for being compatible with pads that are suitable for wire-bonding in electronic packaging. Electroless nickel plating is a selective metal deposition technique which can brings the required thickness and hardness for further pads processing. Here, a 1.7 µm thick nickel layer is deposited on top of 600 nm thick printed and sintered silver nanoparticles using Kapton polyimide as substrate. Prior to plating, a special attention was put on tuning microstructures of printed silver pads by sintering nanoparticles at various temperature ramps (0.1, 10 and 50°C/s) up to 200°C. Results show that fast sintering exhibits the lowest electrical resistivity which is suitable in printed interconnects. However, wire-bonding on nickel pads is best achieved when low sintering ramp is used. This slow sintering presents the highest adhesion strength at the nickel/silver interface since the pores dimensions were restricted to the nanoscale. The validation of the optimized bonding process came from the low electrical contact resistance between plated nickel and the bonded gold wire, and from the wire-pull test which is in accordance with the MIL-STD 883 standard. The actual results show that a compromise has to be found when emphasis is on patterning low resistive interconnects or stiff pads for wire-bonding applications. This compromise is tailored by the sintering engineering.
21 citations
TL;DR: In this paper, four types of thin film coating were carried out on copper for electronic materials by the electroless plating method at a pH range from 3 to 9, and the coating performance was evaluated by electrochemical impedance spectroscopy and potentiodynamic polarization testing in a 3.5 wt.% NaCl solution.
28 Oct 2010
TL;DR: In this article, a low cost process for fabrication of high efficiency silicon-based solar cells from front side ARC patterning through contact line metallization is presented, which utilizes a screen printable etch resist to define the contact pattern and a wet etching solution to remove the exposed ARC layer.
Abstract: This paper presents a low cost process for fabrication of high efficiency silicon-based solar cells from front side ARC patterning through contact line metallization. This process utilizes a screen printable etch resist to define the contact pattern and a wet etching solution to remove the exposed ARC layer. The metallization stack for the contact line pattern consists of a nickel silicide ohmic contact and a nickel and copper metal stack plated using a light induced plating (LIP) process. The nickel silicide contact is formed by annealing a thin nickel seed layer that is deposited on the silicon surface using two different alternative seed layer (ASL) processes, chemically activated and light assisted electroless plating. Through optimization of the ASL processes, a thin, uniform NiSi layer is achieved that is less than 200 nm. This thin NiSi layer should be compatible with shallow emitter silicon solar cells. An LIP process for nickel and copper over the NiSi contact areas is demonstrated.
TL;DR: In this article, a TiO 2 -supported Au on Ni bimetallic nanoparticle catalyst is prepared by electroless nickel plating and the sequential chemical replacement reaction of supported Ni nanoparticles with Au 3+ ions.
Abstract: A TiO 2 -supported Au on Ni bimetallic nanoparticle catalyst is prepared by electroless nickel plating and the sequential chemical replacement reaction of supported Ni nanoparticles with Au 3+ ions. The size of nickel nanoparticles decreases and highly dispersed gold clusters form on the external surface of the nickel nanoparticles during replacement and sequential thermal treatment. Hydrogen chemisorption and X-ray photoelectron spectroscopy show the interface interaction between Au atoms and the surface of nickel nanoparticles, optimization of which can enhance hydrogen adsorption and chlorobenzene hydrodechlorination activity and stability. The surface enrichment of gold species on the Au-Ni bimetallic nanoparticles benefits the removal of Cl species from the surface of active sites during hydrodechlorination and then promotes the stability of the catalyst. A series of Au-Ni bimetallic nanoparticles with different particle sizes are synthesized by using different-sized nickel particles from etectroless plating as precursors. The larger Au-Ni nanoparticles exhibit higher hydrodechlorination activity and stability, suggesting that chlorobenzene hydrodechlorination on Au-Ni nanoparticles is structure sensitive. These findings hold promise for a simple route to design and synthesis of bimetallic systems as highly active and stable catalysts for the catalytic reactions.
TL;DR: In this paper, a fine tungsten powder with an average size of 8 μm was coated by electroless nickel plating with hydrazine and sodium hypophosphite reducing agents to obtain Ni and Ni-P coatings.
Abstract: Fine tungsten powder with an average size of 8 μm was coated by electroless nickel plating with hydrazine and sodium hypophosphite reducing agents to obtain Ni and Ni–P coatings, respectively. The influence of process parameters such as temperature, pH and time of electroless plating was investigated. As coated composite powders were characterised by energy dispersive spectrometer analysis and scanning electron microscopy. It was found that, high homogeneity Ni/Ni–P coatings are deposited around the tungsten particles. Also it was shown that deposited mass on the powders increases as the temperature and pH of bath increase, but with different deposition rates depending on coating type. Furthermore, other results indicate that at higher pH values, the P content in the Ni–P coating decreases, leading less impurity in the final composite powders.
08 Apr 2010
TL;DR: In this paper, a novel technique to selectively deposit nickel by electroless plating on gold seed layers using an oxygen-plasma activation step is presented, which enables the manufacturing of low-resistance vias for heterogeneous three-dimensional (3D) integration of MEMS but it is also a suitable technique for the fabrication of arbitrary shaped nickel-microstructures using chemically stable and cost-effective electroless nickel plating baths.
Abstract: This paper presents a novel technique to selectively deposit nickel by electroless plating on gold seed layers using an oxygen-plasma-activation step. No prior wet surface pre-treatments or metal oxide etches are required. This enables the manufacturing of low-resistance vias for heterogeneous three-dimensional (3D) integration of MEMS but it is also a suitable technique for the fabrication of arbitrary shaped nickel-microstructures using chemically stable and cost-effective electroless nickel plating baths.
TL;DR: In this paper, a dielectric barrier discharge (DBD) plasma at atmospheric pressure was used to improve the hydrophilicity and adhesion of poly (ethylene terephthalate) (PET) nonwoven fabric.
Abstract: In order to develop a more economical pretreatment method for electroless nickel plating, a dielectric barrier discharge (DBD) plasma at atmospheric pressure was used to improve the hydrophilicity and adhesion of poly (ethylene terephthalate) (PET) nonwoven fabric. The properties of the PET nonwoven fabric including its liquid absorptive capacity (WA), aging behavior, surface chemical composition, morphology of the surface, adhesion strength, surface electrical resistivity and electromagnetic interference (EMI)- shielding effectiveness (SE) were studied. The liquid absorptive capacity (WA) increased due to the incorporation of oxygen-containing and nitrogen-containing functional groups on the surface of PET nonwoven fabric after DBD air-plasma treatment. The surface morphology of the nonwoven fibers became rougher after plasma treatment. Therefore, the surface was more prone to absorb tin sensitizer and palladium catalyst to form an active layer for the deposition of electroless nickel. SEM and X-ray diffraction (XRD) measurements indicated that a uniform coating of nickel was formed on the PET nonwoven fabric. The average EMI-SE of Ni-plating of PET nonwoven fabric maintained a relatively stable value (38.2 dB to 37.3 dB) in a frequency range of 50 MHz to 1500 MHz. It is concluded that DBD is feasible for pretreatment of nonwoven fabric for electroless nickel plating to prepare functional material with good EMI-SE properties.
Patent•
12 Mar 2010
TL;DR: In this paper, a process for electroless plating of nickel onto copper features of a printed circuit board which suppresses extraneous nickel plating is described. But the process comprises the steps i) activation of the copper features with palladium ions; ii) removal of excessive palladium ion or precipitates formed thereof with a pre-treatment composition comprising at least two different types of acids wherein one type is an organic amino carboxylic acid and iii) electroless polishing of nickel.
Abstract: The present invention discloses a process for electroless plating of nickel onto copper features of a printed circuit board which suppresses extraneous nickel plating. The process comprises the steps i) activation of the copper features with palladium ions; ii) removal of excessive palladium ions or precipitates formed thereof with a pre-treatment composition comprising at least two different types of acids wherein one type is an organic amino carboxylic acid and iii) electroless plating of nickel.
TL;DR: In this paper, an electroless plated nickel layer was prepared on the surface of microarc-oxidation-fabricated porous magnesium oxide film in a conventional electroless nickel plating solution,consisted of nickel sulfate as main salt and sodium hypophosphite as reducing agent.
Abstract: Generally,the surface pretreatments such as sensitization and activation are necessary for depositing a nickel metal layer on oxide surface by electroless plating,however,for an oxide surface with porous structure it is possible that the pretreatment is not necessary.In this paper,only by use of the surface activity of porous structure,an electroless plated nickel layer can be prepared on the surface of microarc-oxidation-fabricated porous magnesium oxide film in a conventional electroless nickel plating solution,consisted of nickel sulfate as main salt and sodium hypophosphite as reducing agent.Furthermore,the phase,microstructure,electrical conductivity and corrosion resistance of the obtained nickel layer were characterized.The results indicate that the 5μm-thick nickel layer is composed of fine and homogeneously distributed nickel particles,at the same time the microstructure of nickel layer is dense.Nickel layer spreads into the micropores on the surface of porous magnesium oxide film,so that an interleaving interface is formed at nickel/oxide interface.XRD results reveal that the nickel layer contains crystalline Ni and amorphous Ni-P.Four-point probe measurement indicates that the nickel layer exhibits well electrical conductivity.Meanwhile,polarization curve reveals that corrosion potential elevates notably due to the presence of nickel layer.During electroless nickel plating the nickel ions in solution were reduced and deposited in the micropores of porous magnesium oxide film under the action of reducing agent ions,so as to generate tiny primary nickel particles, subsequently,these primary nickel particles continuously grew and spread,and finally formed an entire nickel layer on oxide surface.
TL;DR: In this paper, the surface of the activated carbon was covered by a Ni-P coating, which was uniform, compact, and continuous and had an obvious metallic sheen, and the content of P and Ni was 2.73% and 97.27% in the coating.
Abstract: Nickel-based activated carbon was prepared from coconut shell activated carbon by electroless plating with palladium-free activation. The materials were characterized by scanning electron microscopy (SEM), X-ray energy dispersion spectroscopy (EDS), vibrating sample magnetometry (VSM), and vector network analyzer, respectively. The results show that the surface of the activated carbon was covered by a Ni-P coating, which was uniform, compact, and continuous and had an obvious metallic sheen. The content of P and Ni was 2.73% and 97.27% in the coating. Compared with the untreated activated carbon, the real permeability μ′ and imaginary permeability μ″ of Ni-based activated carbon became greater, whereas the real permittivity e′ and imaginary permittivity e″ became smaller. Also, the plated activated carbon was magnetic, making it suitable for some special applications. In general, the method reported here might be a feasible procedure to coat activated carbon with other magnetic metals, which may find application in various areas.
TL;DR: In this paper, the effect of plating solution volume on metallic ratio and adsorption capacity were evaluated, and the results showed that the metallic ratio was increased with the increase of the plating solutions volume.
Abstract: Nickel-based magnetic activated carbon was synthesized from coconut shell activated carbon by electroless plating with palladium-free activation. The effect of plating solution volume on metallic ratio and adsorption capacity were evaluated. The effect of metallic ratio on specific area, pore volume, and magnetic properties were investigated. The morphologies of activated carbon before and after plating were observed by SEM, and the composition of the layer was analyzed by EDS analysis. The results showed that the metallic ratio was increased with the increase of the plating solution volume. The magnetic activated carbon showed high adsorption capacity for methylene blue and a high iodine number. Those values reached 142.5 mg/g and 1035 mg/g, respectively. The specific area and pore volume decreased from 943 m2/g to 859 m2/g and 0.462 ml/g to 0.417 ml/g, respectively. And the layer was more compact and continuous when the metallic ratio reached 16.37 wt.%. In the layer, there was about 97 wt.% nickel and 3 wt.% phosphorus, which indicates that the layer was a low-phosphorus one. At the same time, magnetism was enhanced, making the product suitable for some special applications.
Patent•
06 Oct 2010
TL;DR: In this article, a method for manufacturing the golden finger of a soldering-pan of a flexible carrying board is described. But this method is not applicable to the case of a printed circuit carrying board.
Abstract: The invention relates to a method for manufacturing a flexible carrying board of which the chip is directly packaged on a flexible printed circuit carrying board (COF), in particular to a method for manufacturing a golden finger of a soldering-pan of a flexible carrying board. The COF packaged flexible carrying board is made of a glueless flexible substrate; a basement membrane of the substrate is made of a polyimide material and has the thickness between 12 and 25 micrometers; and a conductor layer is made of copper, and has the thickness between 9 and 36 micrometers. The method for manufacturing the golden finger of the soldering-pan of the flexible carrying board comprises low-stress electroless nickel plating & gold immersion technology; a raw material is nickel sulfate and a reducing agent is sodium hypophosphite; and in order to reduce the stress of a nickel layer, an additive for reducing the stress is added. The low-stress additive is one or more of benzene sulfonic acid sodium salt, coumarin, formaldehyde, aldehyde and naphthalene disulfonic acid, and the concentration is 0.01 to 0.2 mol/liter. The operating temperature of the low-stress electroless nickel plating is between 80 and 85 DEG C and the pH value is between 4.8 and 5.2.
TL;DR: In this paper, the content of phosphorous in nickel deposit was higher in acidic bath than that in alkaline bath, and the rate of electroless plating in pH and temperature of bath was controlled.
Abstract: Materials used as fuel cell electrode should be light, high conductive, high surface area for reaction, catalytic surface and uniformity of porous structure. Nickel is widely used in electrode materials because it itself has catalytic properties. When used as electrode materials, nickel of only a few im on the surface may be sufficient to conduct the catalytic role. To manufacture the nickel with porous structure, Electroless nickel plating on carbon fiber be conducted. Because electroless nickel plating is possible to do uniform coating on the surface of substrate with complex shape. Acidic bath and alkaline bathe were used in electroless nickel plating bath, and pH and temperature of bath were controlled. The rate of electroless plating in alkaline bath was faster than that in acidic bath. As increasing pH and temperature, the rate of electrolee plating was increased. The content of phosphorous in nickel deposit was higher in acidic bath than that in alkaline bath. As a result, the uniform nickel deposit on porous carbon fiber was conducted.
01 Jan 2010
TL;DR: In this article, the arrangement and chemical composition of these intermetallic phases were studied and discussed as function of the pre-treatment method of SiC particles, and they were added to an Al alloy powder to produce Al/SiC composite by compression and sintering.
Abstract: Electroless nickel (EN) plating was used to coat SiC particles, using three different pre-treatment methods (acidic pre-treatment, surface oxidation, palladium chloride activation). The acidic pre-treatment is able to activate the surface of the particles hardly. Consequently, the electroless nickel deposit formation is only particular. A coherent oxide layer is developed on the surface of the substrate after the surface oxidation. This ensures the homogeneous nickel nuclei formation after using the electroless nickel plating. Finally the palladium chloride activation creates homogeneous palladium nuclei on the surface of the silicon carbide particles. A coherent and continuous nickel layer is formed on the surface containing elemental palladium nuclei. The EN plated SiC particles were added to an Al alloy powder to produce Al/SiC composite by compression and sintering. During sintering (580°C 5h), the nickel coating of the silicon carbide particles and the matrix react with the formation of different Al-Ni phases. The arrangement and chemical composition of these intermetallic phases was studied and discussed in this paper as function of the pre-treatment method of SiC particles.
Patent•
22 Jul 2010
TL;DR: In this paper, a two-layer flexible copper-clad laminate substrate (two-layer FCCL) which has a smooth, glossy appearance and is excellent in peeling resistance and is produced by conducting thick copper plating on a resin film surface using an acidic copper-plating bath composition, was presented.
Abstract: PROBLEM TO BE SOLVED: To provide a two-layer flexible copper-clad laminate substrate (two-layer FCCL) which has a smooth, glossy appearance and is excellent in peeling resistance and is produced by conducting thick copper plating on a resin film surface using an acidic copper plating bath composition, and a method for producing the two-layer FCCL by a wet plating method using an acidic copper plating bath composition, wherein electroplating step in the wet plating method is carried out in a single step. SOLUTION: The method for producing the two-layer FCCL through the wet plating method using the acidic copper plating bath composition and a resin film coated with a conductive metal serving as a seed layer includes: a step of forming an electroless nickel plating seed layer on a hydrophilized surface of a resin film; and a step of performing wet electroplating, without performing primary copper plating, in the acidic copper plating bath composition so as to thickly deposit a conductive copper layer on the seed layer. COPYRIGHT: (C)2010,JPO&INPIT
TL;DR: In this article, the process to recover nickel ions from electroless plating waste liquor was investigated by using a solvent extraction method, and the extractant mixtures of acidic extractant such as D2EHPA and PC-88A, and another extractants with electron-donating ability such as nicotinic acid dodecyl ester and iso-nicotinic acids dodecynic ester were used for this purpose.
Abstract: Electroless nickel plating waste liquor contains a large amount of nickel ions, but nickel ions in waste liquor have not been recovered for technical and economic reasons. If the recovery of nickel ions is effectively carried out, nickel ions could be recycled as a nickel source for electroless plating liquor. The process to recover nickel ions from electroless plating waste liquor was investigated by using a solvent extraction method. The existence of various phosphate species and organic acids in the waste liquor causes the incomplete extraction of nickel ions with any single extractant due to the complex formation between nickel ions and them. The application of solvent extraction using a synergistic effect makes possible to separate and recover 90% or more of nickel ions in the waste liquor. The extractant mixtures of acidic extractant such as D2EHPA and PC-88A, and another extractants with electron-donating ability such as nicotinic acid dodecyl ester and iso-nicotinic acid dodecyl ester are used for this purpose.
TL;DR: In this paper, an attempt has been made for an electroless nickel plating process on two steel substrates (with and without a high temperature oxide scale at the top surface) to identify the role of a high- temperature iron oxide scale on coating kinetics.
Abstract: An attempt has been made for an electroless nickel plating process on two steel substrates (with and without a high temperature oxide scale at the top surface) to identify the role of a high temperature iron oxide scale on coating kinetics. This study investigated if an iron oxide scale on the steel surface acts as a catalyst and promotes faster metal deposition. Coatings were characterized by scanning electron microscopy (SEM), glow discharge oxy emission spectroscopy (GDOES), and X-ray diffraction (XRD) and an iron oxide scale was characterized by Raman spectroscopy. Chemical composition and structure of both the coatings are the same but the coating obtained on a steel substrate having a high temperature oxide scale at the top is two times thicker. The electrochemical performances of both the coated steel substrates were evaluated by Tafel and electrochemical impedance (EIS) tests in an aggressive chloride environment. The coating obtained on a steel substrate containing a high temperature oxide scale at the top exhibits better resistance against chloride attack and charge transfer than the coating obtained on the steel substrate without a high temperature oxide scale at the top. This can be attributed to the highest thickness of this coating, which has the same chemical composition of the other coating, expected to give better resistance against chloride attack and charge transfer.
Patent•
28 Oct 2010
TL;DR: In this paper, the authors proposed a method in which an elastic layer is adhesive to an axial core body and easy to cut and which removes part of the elastic layer without an adhesive or a releasing agent.
Abstract: PROBLEM TO BE SOLVED: To provide a method in which an elastic layer is adhesive to an axial core body and easy to cut and which removes part of the elastic layer without an adhesive or a releasing agent, on producing an elastic roller by cutting and removing part of the elastic layer formed on the outer peripheral surface of the axial core body and exposing both ends of the axial core body. SOLUTION: In the production method for the elastic roller, an axial core body 11 is coated with an electroless nickel plating on its surface, the non-electrolytic nickel plating on both ends to be exposed are treated with one of heat treatment, irradiation treatment or chemical treatment, a layer of raw material rubber composition is formed as an elastic layer 12 on the outer peripheral surface of axial core body not through other substances and part of crosslinked rubber layer is cut and removed after heat crosslinking; provided that the degree of surface oxidation (Ni oxide/Ni metal) of nickel plating as obtained by the X-ray electron spectroscopy is 1.0 to 3.0 at both ends 31 to be exposed and 0.2 to 0.6 at the center 33 of axial core body, and that the raw material rubber composition contains one or both of sulfur and a vulcanizing agent having sulfur atom in its molecule. COPYRIGHT: (C)2011,JPO&INPIT
Patent•
24 Nov 2010
TL;DR: In this article, a method for preparing nano metallic nickel in spent electroless nickel plating solution is proposed, which comprises the following steps: adding 020 to 033 grams of reducer thiourea dioxide into every 100ml of the spent ENEM solution; then, adjusting the spent electrolyless nickel solution to be alkalic with 3 to 7 grams of sodium hydroxide, and heating the ENE solution to the temperature of between 70 and 100 DEG C; reacting at constant temperature for 5 to 20 minutes, and cooling the solution to a temperature
Abstract: The invention discloses a method for preparing nano metallic nickel in spent electroless nickel plating solution The method comprises the following steps: adding 020 to 033 grams of reducer thiourea dioxide into every 100ml of the spent electroless nickel plating solution; then, adjusting the spent electroless nickel plating solution to be alkalic with 3 to 7 grams of sodium hydroxide, and heating the spent electroless nickel plating solution to the temperature of between 70 and 100 DEG C; reacting at constant temperature for 5 to 20 minutes, and cooling the solution to the temperature of between 10 and 30 DEG C; filtering the spent electroless nickel plating solution; and washing the filtered substances with deionized water and absolute ethanol respectively; and drying the substances in a vacuum drier to prepare the nano metallic nickel The method effectively solves the problem of spent electroless nickel plating solution pollution, simultaneously recycles noble metal nickel, and realizes double assurance of social benefit and economic benefit for enterprises Furthermore, the reducer thiourea dioxide has lower requirement to the reaction condition, less investment, no toxic or side effect and environmental protection
Patent•
01 Jul 2010
TL;DR: In this article, an electroless nickel plating solution composition, a flexible printed circuit board and a method of manufacture thereof are provided to replace a double plating process of nickel and direct gold coating with a single plating procedure.
Abstract: PURPOSE: An electroless nickel plating solution composition, a flexible printed circuit board and a method of manufacture thereof are provided to replace a double plating process of nickel and direct gold coating with a single plating process. CONSTITUTION: An electroless nickel plating solution composition comprises water-soluble Ni-chemical compound, reducing agent, complexion agent, vertical growth derivative, vertical growth aiding agent. The vertical growth derivative comprises the compound having bismuth ion. A nickel plated layer(150) is formed using electroless nickel plating solution composition. The vertical growth derivative is composed of 0.001~1 weight% based on the composition range of electroless nickel plating solution composition. The vertical growth aiding agent is ether thallium ion, iron ion or copper ion.
Patent•
29 Apr 2010
TL;DR: In this article, the authors present novel metal coatings containing Nickel and Silica-particles of 10 - 400 nm size as defined in the specification, and workpieces containing such coatings; electroless nickel plating baths suitable for producing such coats; and processes for manufacturing such plating bath and coatings / workpieces.
Abstract: The present invention provides novel metal coatings containing Nickel and Silica-particles of 10 - 400 nm size as defined in the specification; workpieces containing such coatings; electroless nickel plating baths suitable for producing such coatings and workpieces; processes for manufacturing such plating baths and coatings / workpieces.