Abstract: The present invention discloses a process for electroless plating a metal on the surface of almost all the common nonconductive material substrates by brushing or spraying composite chemical solutions onto said surface. When practicing the present invention, metal can be quickly deposited on the surface and firmly bound with the substrate. In addition, the composite chemical solutions used in the invention can be prepared from raw chemicals which are nontoxic and do not cause environmental pollution. Since the process does not require immersing or dipping, it allows metal to be deposited either on the entire surface or on a portion of a surface of the substrate without any restriction of the dimensions of the substrate. In one embodiment, the substrates may be glass, silicates or ceramics and may be sensitized using a solution which comprises about 25-175 g/l SnCl.sub.2, about 35-110 g/l of about 36% HCl, and about 50-100 g/l of about 95% ethanol.

Abstract: New spray powder formulations are described which, after application in the form of a thin layer to substrate surfaces with the aid of processes basset on electrostatic attraction and storing of this layer by heat or high-energy radiation, allow the deposition of firmly adhering layers of metal by currentless, wet-chemical metallization. The essential constituents of such a formulation are a pulverulent, non-conductive material and (semi-) noble metal compounds.

Abstract: A wet-chemical metallization process is used for electrically non-conductive, previously chemically activated plastic substrate sheets. After metallization, the metallizing solution is separated from the substrate sheet by the influence of gravity or centrifugal force, and the sheet is rinsed with rinsing water. The metallizing solution and the rinsing water are each collected separately and subjected to a treatment for the purpose of reuse. To this end, the metallizing solution is distilled and reused as rinsing water. The rinsing water is worked up into a reusable metallizing solution by the addition of chemical metallizing components, thereby saving costs for make-up water (i.e. distilled water) and reducing pollution of the environment by contaminated effluents.

Abstract: This invention proposes the addition of imidazole and imidazole derivatives to various activator solutions for the selective activation and plating of metallic surfaces. The invention is particularly useful in plating exposed copper surfaces on printed circuit boards without substantial extraneous plating on the solder mask surfaces.

Abstract: The invention is directed to a process for patterning a substrate in a selective pattern. In one embodiment, the process comprises the steps of forming a patterned coating over a substrate surface whereby portions of the substrate are covered by the patterned coating and portions of the substrate remain uncoated. A layer of a ligating material is coated over at least those portions of the substrate free of the patterned coating. The ligating layer is one that is capable of ligating with an electroless metal plating catalyst. The article so formed is then contacted with an electroless metallization catalyst and then with an electroless plating solution to form a patterned metal deposit on the substrate.

Abstract: A method for forming a thin film layer on a dielectric substrate. A nonconducting layer of material is blanket deposited on the dielectric substrate followed by a layer of polymeric dielectric material which is then patterned to partially expose the underlying layer of nonconducting material. The exposed underlying layer of material is contacted with a metallic salt solution. A key part of the present invention is the layer of nonconducting material which catalyzes the deposition of a seed layer from the metallic salt solution. Then, additional metallization may be easily electrolessly plated on the seed layer.

Abstract: A method of manufacturing a printed wiring board includes the following steps. A circuit pattern consisting of one material selected from the group consisting of copper and a copper alloy is selectively formed on an insulating substrate, and a solder resist is then formed on the insulating substrate except for a region in which the circuit pattern is formed. A copper oxide and a copper impurity produced on surfaces of the solder resist and the circuit pattern formed on the insulating substrate are removed. A copper oxide coating is uniformly formed on the surface of the circuit pattern from which the copper oxide and copper impurity are removed. A oxidation-proof coating consisting of an imidazole-based pre-flux is formed by substituting the copper oxide coating on the surface of the circuit pattern with imidazole.

Abstract: A electroless plating method of an Ni--Al intermetallic compound includes steps of a) providing a reducing solution containing a reducing agent and reducing nickel ions, b) adding a proper amount of aluminum powder to the reducing solution, and c) permitting the reducing agent to reduce the reducing nickel ions to be deposited on the aluminum powder. Such electroless plating method permits the Ni--Al compound to be produced inexpensively/efficiently/fastly.

Abstract: A process is disclosed for treating aramid fibers such that metal plating applied thereto is durable, highly conductive, and strongly adherent. The process involves contacting the fibers with an acid, neutralizing and washing the fibers with water, and then plating the fibers by an electroless plating process. The acid treatment of the fibers promotes adhesion between the metal and the fibers and promotes high electrical conductivity for the plated metal.

Abstract: Substrates are activated for subsequent metallization by contacting the substrate with a electrolyte in which reducing agents which are electrochemically generated in the electrolyte. The reducing agents are sorbed by the substrate which is contacted with a seeding medium to dispose on the substrate seed, preferably palladium seed for subsequent electroless and electrolytic metallization.

Abstract: A process for promoting the adhesion of metal to thermoplastic substrates such as polyetherimides. The improvement comprises conditioning the substrate by treating with an inorganic hydroxide solution prior to subsequent steps of etching and deposition of a metal coating. Use of the conditioner promotes increased adhesion between the substrate and the metal without loss of flexural strength of the substrate throughout subsequent processing steps.

Abstract: Disclosed is a composition and process useful in activating nickel-phosphorous surfaces for subsequent plating thereon. A combination of sulfuric acid and ammonium sulfate is utilized to render otherwise non-catalytic nickel-phosphorous surfaces catalytic to subsequent plating.

Abstract: A process is disclosed for making metal plated fibrids wherein the plating is conductive and highly durable. The process involves contacting the fibrids with an 80 to 90% sulfuric acid solution, neutralizing and washing the fibrids with water, and then plating the fibrids by an electroless plating process. The acid treatment of the fibrids promotes adhesion between the metal and the fibrids and promotes high electrical conductivity for the plated metal.

Abstract: Substrates comprising blends of at least one polyphenylene ether and at least one poly(alkenylaromatic compound) (e.g., polystyrene) are treated with aqueous tetravalent cerium in a concentration of at least about 0.1 M, preferably acidified with nitric acid, to improve adhesion to metal coatings subsequently deposited nonelectrolytically; for example, by electroless deposition. The metallized articles are heat treated following metal deposition. Further metal coatings may be deposited, preferably followed by further heat treatment.

Abstract: The method serves for the electroless deposition of a metal layer (7) from a metallization liquid on a top side of a flat article to be metallized, more in particular a flat disc, for example, a master disc (1) which is used for the reproduction of optical discs. According to the method the top side of the article is first made hydrophilic, if so necessary, after which, with the article supported in a horizontal position, a quantity of metallization liquid is provided on the top side which was previously made hydrophilic as a stable liquid layer (16) bounded by the edges of the article, after which the deposition of the metal from the liquid on the article takes place and the liquid layer is the removed entirely from the surface.

Abstract: A process for simultaneously selectively depositing a high purity nickel containing alloy (i.e. a nickel-boron alloy having a nickel content in excess of 99.5 percent) over a preformed metallurgy pattern (including the individual, electrically isolated contact pads and the seal band area thereon) on the top-side dielectric surface of a multi-layer ceramic module. The metallurgy pattern on such top-side surface of such module is appropriately catalyzed and then immersed in a bath which is essentially lead-free and which includes a source of nickel ions, a borane reducing agent, and an effective amount of an organic divalent sulfur compound, preferably thiodiglycollic acid.

Abstract: Conductive fibers of a combination of aramid and polyvinyl pyrrolidone (PVP) are disclosed having a strongly bonded metal coating applied by electroless plating. PVP increases adhesion of the fiber surface to the electroless plating. The preferred aramid is poly(p-phenylene terephthalamide).

Abstract: A color filter in accordance with the present invention comprises an activated film layer (2) arranged on a transparent substrate (1), said activated film layer (2) having a color pattern formed thereon by permeating a dye thereinto, and a thin metal film pattern (3) formed on a portion, of said activated film layer (2), which requires the formation of a black mask. Accordingly, the color filter integrated into various display devices such as a liquid crystal display is capable of displaying an image having a high contrast. Further, a method for forming a color filter in accordance with the present invention comprises the steps of forming an activated film layer (2) on a transparent substrate (1); permeating a dye into said activated film layer (2) to form a color pattern; and performing an electroless plating to form said thin metal film pattern (3) which functions as a black mask.

Abstract: Increases in surface resistivity of electroless nickel coatings on polycarbonate-containing substrates are inhibited by employing two electroless nickel plating solutions. The first solution is one which deposits a metal layer containing phosphorus, if any, in an amount up to 5% by weight and is used to deposit a layer at least 0.5 micron thick. The second solution is one which deposits a layer containing phosphorus in the amount of at least 5% and preferably at least 6% by weight. Another metal layer may be interposed between the two nickel layers.

Abstract: Metallic silver is deposited upon the surface of a nonconducting substrate using a multi-step wet deposition process. The surface is cleaned, and then activated in an aqueous solution containing stannous tin. The silver is deposited as a colloidal material from an aqueous solution of a silver-containing salt, a reduction agent that reduces the salt to form the metallic silver, and a deposition control agent that prevents the silver from nucleating throughout the solution. After the substrate is coated, the coating is stabilized in an aqueous solution of a salt of a metal from the platinum group or gold, dissolved in dilute hydrochloric acid. The process is particularly effective for depositing uniform films of 2 to 2000 Angstroms thickness, which strongly adhere to the substrate.

Abstract: A process and catalyst for electroless plating of metal over a substrate. The process involves providing a catalyst that is the product of reaction of a noble metal with bromide ions where the ratio of bromide ions to noble metal ions is at least 100 to 1 and the noble metal is present in a concentration sufficient to catalyze an electroless plating reaction, contacting a substrate to be plated with the catalyst, and reducing the catalyst prior to or during plating of the substrate.

Abstract: An improved process is disclosed for treating aluminum for memory disk applications and for producing metal plated aluminum memory disks. It has been found that a solution prepared from methane sulfonic acid and sodium peroxydisulfate can be used as a direct replacement for a nitric acid bath in the processing of aluminum substrates for memory disk application. In accordance with the present invention, the methane sulfonic acid/sodium peroxydisulphate solution can be used to deoxidize the aluminum substrate prior to zinc deposition and also to remove the first zinc film in either alkaline or acid double zinc plating processes.

Abstract: Disclosed is a method for the plating of a substrate with a composite coating bearing a metallic matrix with finely divided particulate matter dispersed therein. The plating bath is derived by the admixing of a prestabilized particulate matter composition or a precursor thereof along with the required plating chemicals. The use of a prestabilized particulate matter composition offers a convenient way of shipping treated powders devoid of liquids and thereby minimizing shipping costs and aging effects commonly associated with liquid dispersions. The use of the novel prestabilized particulate matter composition along with the plating chemistry provides results substantially the same as those observed from freshly prepared liquid dispersions and their incorporation along with the plating chemicals.

Abstract: Methods and compositions for electroless metallization. In one aspect, the invention is characterized by the use of chemical groups capable of ligating with an electroless metallization catalyst, including use of ligating groups that are chemically bound to the substrate. In a preferred aspect, the invention provides a means for selective metallization without the use of a conventional photoresist patterning sequence, enabling fabrication of high resolution metal patterns in a direct and convenient manner.

Abstract: The metal (for example, copper) to base material adhesion in an additive printed wiring board is improved by contacting the base material with a solution containing a ureidosilane, preferably also comprising a disilyl crosslinking agent, followed by drying the solution to remove solvent, before contacting the base material with an activating agent for an electroless deposition step. Heating of the board, after the deposition of the metal, for example by baking in an oven or in an autoclave, gives the highest level of adhesion between metal and base material.

Abstract: By virtue of an activating pretreatment with a polymer-stabilized Pd sol, patterns, such as transparent patterns of indium-tin oxide, can be deposited on glass by electroless metallization. For example polyvinyl alcohol is used as the polymer.

Abstract: A method of selectively seeding or activating metal interconnections patterned on polyimide dielectric surfaces using an aqueous solution of palladium sulfate, palladium perchlorate, palladium trifluoromethane sulfonate, palladium nitrate or other palladium salts having poorly coordinating counter ions. This strongly selective seeding and the corresponding ability to reliably remove all traces of the seeding material from the polyimide surface eliminates shorting, bridging and reduction of breakdown voltage during electroless plating of a thin layer of nickel or cobalt.

Abstract: A process for electroless gold plating using plating solution comprizing cyanoaurate, alkaline cyanide, reducing agent, alkaline hydroxide, crystal condition controlling agent and stabilizer characterized in that an aldehyde or a ketone compound is added together with replenished gold salt, and hydrogen peroxide is also added, if necessary.

Abstract: An electroless process has been developed to deposit nickel and gold onto optical fibers using aqueous chemistry. The key to the process is a sensitization of a surface of an optical fiber using a dilute aqueous stannous fluoride solution in absence of oxygen. Stannous fluoride solution is prepared by dissolving crystalline SnF.sub.2 in deionized water. Subsequent treatment includes immersion of sensitized optical fiber in a palladium chloride/HCl aqueous solution and commercially available electroless nickel and electroless gold solutions. The process is compatible with either chemical or fusion lensing operations by using a strippable polymer coating to selectively metallize near the fiber end. The solder joints to the metallized fiber are hermetic as determined by helium leak testing, and solder pull-test strengths typically range from 3-5 pounds, depending on the type of solder.

Abstract: A method for the manufacture of printed circuit boards is provided comprising conditioning the board, activating with a catalytic metal, post-activating, stabilizing and etching the copper surfaces before the desired circuit is formed on the board. This process eliminates the need for a flash coating of copper in the through holes before the use of protective coatings such as imaging resists and soldermasks.

Abstract: The present invention describes a process for protecting aluminum nitride circuit substrates during electroless plating using a sol-gel technique. The aluminum nitride substrate is coated with a metal. The coated substrate is etched to form a circuit pattern thereby exposing the aluminum nitride. The etched substrate is placed in a solution of tetraethylorthosilicate and withdrawn. The substrate is dried in air and then baked in an oven to remove all of the organic solvents leaving a stoichio metric film of silica on the exposed substrate. The substrate is then placed in an electroless plating solution and the circuit pattern is plated to a predetermined thickness.

Abstract: A method for roughening the surface of a resin molded article to make it susceptible to metallizing is disclosed, comprising contacting a resin molded article at least the surface of which to be toughened mainly comprises a block copolymer comprising 100 parts by weight of a polyphenylene sulfide resin and from 30 to 100 parts by weight of a polyphenylene sulfide ketone resin with a solvent capable of dissolving a polyphenylene sulfide ketone resin more than a polyphenylene sulfide resin.

Abstract: A method of making a colloidal metal dispersion that is useful as a toner fluid. The method involves reducing a palladium and/or platinum metal of a metallo-organic palladium and/or platinum metal salt in a dispersing medium that contains a soluble surfactant and a carrier liquid. The palladium and/or platinum metal of the metallo-organic metal salt is reduced in the dispersing medium to form elemental metal particles. The soluble surfactant is present in the dispersing medium in an amount sufficient to charge and stabilize the elemental metal particles as a colloidal metal dispersion.

Abstract: A process is disclosed which is beneficially employed in sensitizing plastic surfaces prior to etching which sensitization enhances the coverage and adhesiveness of the subsequent plate. The composition and process proposed use Limonene, solutions of Limonene and Emulsions of Limonene for the sensitizer.

Abstract: A dielectric substrate is conditioned for subsequent electroless plating thereon by contacting with a catalytic metal salt and then with a reducing agent and with an electroless metal plating bath followed by contacting with a second catalytic metal salt. In addition, a dielectric substrate is conditioned for electroless plating thereon by obtaining a substrate of a dielectric material that contains metal particles therein and contacting with a catalytic metal salt.

Abstract: Addition polymer substrates comprising structural groups derived from olefinic nitriles and conjugated dienes, especially ABS resin substrates, are treated with aqueous tetravalent cerium in a concentration of at least about 0.1 M, preferably with a tetravalent cerium solution, to improve adhesion to metal coatings subsequently deposited non-electrolytically; for example, by electroless deposition. The metallized articles are heat treated following metal deposition. Further metal coatings may be deposited, preferably followed by further heat treatment.

Abstract: Improved adhesion of electroless metal deposited on an organic dielectric layer with phase separated morphology is accomplished by the spontaneous formation of a morphologically and topographically rough surface. In one embodiment a ternary solution of a polar solvent and two polymer precursors of the same polymer which are separable in two phases of different order are cast in film on a substrate and heated to form two phases of different order to spontaneously produce a rough surface. Upon exposure to an alkaline solution, one phase is etched at a faster rate than the other. Seeding and electroless deposition of a metal on the rough surface results in improved adhesion of the metal to the dielectric layer. In a second embodiment a quaternary solution of a polar solvent, a seeding agent, two polymer precursors of the same polymer which are separable in two phases of different order are cast in a thin film on a substrate and heated to form three phases.

Abstract: A method of processing the surface of a metallic rod, wherein coating films (2, 22 and 32) are applied onto portions other than the shape where grooves are to be formed on the surface of the rod, the surfaces of the rods (1, 21 and 31) which are not coated are dissolved and processed by chemical polishing or etching, whereby patterns of very shallow grooves (6, 24 and 34) are formed on the surface of the rod, so that making of grooves on the surface of a very heavy rod, a long rod and a curved rod, which have been considered difficult by the conventional machining, can be easily and accurately carried out. Furthermore, after the making of the grooves, the surface of a rod (41) is plated in a state (42) of being coated by photoresist films and screens, whereby the grooves and the recessed portions (43) are plated (44), and thereafter, the coating films (42) are removed by buffing (45) and the like and the plated surface is finished, thus effectively plating the grooves and the recessed portions.

Abstract: A process for protecting aluminum nitride circuit substrates during electroless plating using surface oxidation. The aluminum nitride substrate is coated with a metal stack. The coating on the substrate is etched to form a circuit pattern. The patterned substrate is then fired in an oxidizing atmosphere at a temperature and time sufficient to convert the exposed aluminum nitride to aluminum oxide. After this conversion, the substrate is plated in an electroless solution forming a microwave circuit ready for component attachment and packaging.

Abstract: In a preferred method, a zinc-rich alloy coating is applied to a substrate using an electrolysis deposition solution which contains a metal salt of zinc and a metal salt of nickel each in an amount sufficient to provide a weight ratio of zinc to nickel (Zn:Ni) of at least about 1:1; a phosphorus-containing reducing agent in an amount sufficient to cause reduction of the zinc and the nickel to ions thereof; sufficient complexing agent to maintain the nickel ions and the zinc ions in solution; and a buffer in an amount sufficient to achieve a desired pH. Preferably, the surface of the substrate is pretreated or precatalyzed before deposition by a sensitizing step using tin and an activating step using palladium.

Abstract: Method of producing a modified polyimide layer to improve adhesion of a metal layer thereon. A limited quantity of water is added to a halogenated polyamic acid to form a reaction product, which is then sprayed, degreased, oxidized and cured into a modified polyimide layer. The chemically modified surface by the aforementioned method is then electrolessly plated with a primary metal layer followed by one or more electrolessly or electrolytically applied secondary metal layers until the metal layer of a desired thickness is attained. The present invention further discloses articles such as an EMI shielded enclosure and an insulated mold surface, having metal layers as an EMI shield and an insulating surface, respectively.

Abstract: Sulfonated polyamides, e.g. aliphatic polyamides such nylon-6 and nylon-6,6, partially aromatic polyamides and polyaramides such as poly(phenyldiamidoterephthalate), provided with sulfonate radicals chemically bonded as amine pendant groups to nitrogen atoms in the polymer backbone are useful for stainblocking polyamide textile articles and as precursors for providing electrolessly-deposited metal-coatings on palladium sulfonate modified surfaces. Nickel-coated polyaramide textile material have surprisingly exceptional flame resistance.

Abstract: The adhesion of metal coatings, such as those produced by electroless or physical vapor deposition, on polypyromellitimide surfaces is improved by prior treatment of the surface with concentrated sulfuric acid, followed by aqueous alkali metal hydroxide of at least about 2M concentration. Further metal may be deposited on the surface, for example by electrolytic or physical vapor deposition, following the original metal deposition.

Abstract: The invention provides a process for electroless plating tin, lead or tin-lead alloy on copper or copper alloy using an electroless plating bath containing a water soluble tin and/or lead salt, an acid capable of dissolving the salts, and a complexing agent. The tin and/or lead content in the bath is maintained high enough to chemically deposit thick films by replenishing the tin and/or lead salt in proportion to an increase in concentration of copper ion dissolving out in the bath. Also provided is an electroless tin, lead or tin-lead alloy plating process in which a water soluble copper salt is added to a fresh bath.

Abstract: Certain organic polymeric materials are capable of reversibly accepting or donating electrons from a reducing entity. The redox sites in the polymer accept electrons and, as a result, a change in the properties of the polymer occurs. This change is useful in modifying or etching the polymeric material The material can be modified by incorporation of metallic seeds into the material at a controlled depth. The seeds are incorporated by interaction of cations of the metals with the redox sites in the polymer, which cause the reduction of the cations to form the neutral metallic seeds. Subsequent exposure of the polymeric material containing the seeds to an electroless bath causes further deposition of metal having the desirable characteristic of good adhesion to the polymeric material. Etching of the polymeric material can be carried out as a result of an increase in solubility of the polymer in aprotic solvents when its redox sites have accepted electrons.

Abstract: A process and composition for preparing a nonconducting surface for electroplating. The process comprises contact of the nonconductor with a reaction product of a stannous salt, a noble metal salt and halide ions in acidic solution having a pH not exceeding 3.5. The noble metal salt is present in a amount of from 0.01 and 2.5 grams per liter. The weight ratio of tin to noble metal preferably varies between 150:1 to 700:1. Following contact with the tin-noble metal composition, the surface is contacted with a solution of a sulfur salt able to react with tin and the noble metal to form a sulfide and then electroplated.

Abstract: This invention relates to a novel electroless plating method which requires no pre-treatment step for the surface-corrosion on the surface to be plated, wherein a metal layer is formed by applying, onto the surface to be plated, a solution of a composition consisting of a styrene type elastomer used generally as a component for the hot melt type adhesive agent, or the styrene type elastomer and a stickiness imparting resin of a molecular structure similar to that of the elastomer; drying the solution as applied; and effecting the electroless plating on the coated film thus obtained, the method being able to substitute the conventional electroless plating as an advance step of the electrolytic plating for synthetic resin. The particular object of the present invention is to utilize the method in the field of the electroless plating for the purpose of preventing the plating operation from the electromagnetic wave disturbances.

Abstract: This invention relates to electroless nickel plating of metals which are normally noncatalytic for electroless nickel initiation. It is especially useful in the electronics industry, such as for production of electroless nickel/electroless gold tabs or surface mount pads on printed circuit boards, and for use in electroless nickel plating over copper for radiofrequency interference shielding. More particularly, it comprises ammonium halide salt solutions of a palladium salt with another Group VIII precious metal salt and acid and optionally an alkali halide salt for effectively and completely catalyzing the initiation of electroless nickel plating on copper substrates.

Abstract: There is disclosed a method for forming a ferrite coatings on a substrate, which comprises:(a) bringing a substrate into contact with water or an aqueous solution, and(b) adding a ferrous ion solution, an oxidizer solution and a pH controller so that pH and an oxidation-reduction potential may be included within the range specified by A (6, -440 mV), B (6, -130 mV), C (11, -430 mV) and D (11, -740 mV) in a pH - oxidation-reduction potential graph.

Abstract: A process for metal plating characterized by use of an accelerator solution of a metal reducible by stannous tin between a step of catalysis and metal deposition.