May 5,  2011  20  US 2011/0104454 Al  [0296]  The metal (electroless plating catalyst) or a metal  salt ( electro less plating catalyst precursor) can be applied to  the layer to be plated by preparing a dispersion by dispersing  the metal in a suitable medium, or preparing a solution includ› ing dissociated metal ions by dissolving the metal salt in a  suitable solvent; and then applying the dispersion or the solu› tion to the layer to be plated. Alternatively, the substrate with  the layer to be plated formed thereon may be immersed in the  dispersion or the solution.  [0297]  It is also possible to add a plating catalyst or the  precursor thereof to a composition for forming a layer to be  plated, and then applying the composition to the substrate in  step (1 ). Namely, a patterned layer to be plated including the  plating catalyst or the precursor thereof can be formed on the  substrate by contacting the composition including the specific  polymer and the electroless plating catalyst or the precursor  thereof to the substrate, and then by performing light expo› sure and development to the composition. In this way, steps  (1) to (3) can be conducted in a single process.  [0298]  When the substrate is a resin film and the layer to be  plated is formed on both sides of the resin film, an immersion  method as mentioned above is preferably used, so that the  electroless plating catalyst or the precursor thereof can be  contacted at the same time to the layers to be plated that are  formed on both sides of the resin film.  [0299]  By contacting the electroless plating catalyst or the  precursorthereofto the layer to be plated as mentioned above,  the electro less plating catalyst or the precursor thereof can be  adsorbed to the interactive group in the layer to be plated by  means of interaction due to an intermolecular force such as  van der Waals’ force or a coordination bond of lone-pair  electrons.  [0300]  From the viewpoint of achieving the above adsorp› tion to a sufficient level, the concentration of metal in the  dispersion, solution or composition, or the concentration of  metal ions in the solution, is preferably from 0.001 to 50% by  mass, and more preferably from 0.005 to 30% by mass.  [0301]  The time for contacting is preferably from about 30  seconds to about 24 hours, and more preferably from about 1  minute to about 1 hour.  [0302]  When a palladium compound is used in the solution,  dispersion or composition that includes the electro less plating  catalyst or the precursor thereof, the content of the palladium  compound is preferably from 0.001 to 10% by mass, more  preferably from 0.005 to 5% by mass, and yet more preferably  from 0.1 to 1 % by mass, with respect to a total amount of the  solution, dispersion or composition.  [0303]  When a silver compound is used in the solution,  dispersion or composition that includes the electro less plating  catalyst or the precursor thereof, the content of the silver  compound is preferably from 0.1 to 20% by mass, more  preferably from 0.1 to 20% by mass, and yet more preferably  from 0.5 to 10% by mass, with respect to a total amount of the  solution, dispersion or composition.  [0304]  In either of the above two cases, when the content of  the metal compound is too small, precipitation in the subse› quent plating may not easily occur, and when the content of  the meal compound is too large, precipitation may occur in an  undesired portion, or removability of etching residues may  become impaired.  [0305]  The amount of the electro less plating catalyst or the  precursor thereof to be adsorbed may differ depending on the  type of electroless plating catalyst or precursor thereof.  [0306]  The amount of silver ions to be adsorbed to the layer  to be plated is preferably 300 mg/m $^{2 }$or more, more preferably  500 mg/m 2  or more, and yet more preferably 600 mg/m 2  or  more, from the viewpoint of performing satisfactory precipi› tation in the electroless plating. From the viewpoint of form› ing a metal pattern that is highly adhesive to the substrate, the  amount of silver ions to be adsorbed is preferably 1000  mg/m $^{2 }$or less.  [0307]  The amount of palladium ions to be adsorbed to the  layer to be plated is preferably 5 mg/m 2  or more, and more  preferably 10 mg/m $^{2 }$or more, from the viewpoint of perform› ing satisfactory precipitation in the electroless plating. From  the viewpoint of forming a metal pattern that is highly adhe› sive to the substrate, the amount of palladium ions to be  adsorbed is preferably 1000 mg/m $^{2 }$or less.  [0308]  Other Catalysts  [0309]  In the invention, when electroplating is directly con› ducted in the subsequent step ( 4) without performing electro› less plating, a zero-valent metal may be used as the catalyst  for the electroplating. Examples of the zero-valent metal  include Pd, Ag, Cu, Ni, Al, Fe and Co. Among these, those  capable of multidentate coordination are preferable, and Pd,  Ag and Cu are particularly preferred in view of adsorbability  (attachability) to the interactive group (such as a cyano  group).  [0310]  Organic Solvent and Water  [0311]  The plating catalyst or the precursor thereof can be  applied in the form of a dispersion or a solution ( catalyst  solution), as mentioned above.  [0312]  In the invention, an organic solvent or water can be  used for the catalyst solution.  [0313]  By including the organic solvent, permeability of  the layer to be plated with respect to the plating catalyst or the  precursor thereof can be improved, and the plating catalyst or  the precursor thereof can be adsorbed to the interactive group  in the layer to be plated with high efficiency.  [0314]  Water may be used in the catalyst solution according  to the invention. The water preferably includes no impurities.  From this point of view, RO water, deionized water, distilled  water and purified water are preferred, and deionized water  and distilled water are particularly preferred.  [0315]  The organic solvent for use in preparing the catalyst  solution is not particularly limited as long as it can penetrate  into the layer to be plated. Specific examples thereof include  acetone, methyl acetoacetate, ethyl acetoacetate, ethylene  glycol diacetate, cyclohexanone, acetylacetone, acetophe› none, 2-(1-cyclohexenyl)cyclohexanone, propylene glycol  diacetate, triacetine, diethylene glycol diacetate, dioxane,  N-methy 1 pyrrolidone, dimethy 1 carbonate, and dimethy 1 cel› lo solve.  [0316]  Other examples of the organic solvent include diac› etone alcohol, y-butyrolactone, methanol, ethanol, isopropyl  alcohol, n-propyl alcohol, propylene glycol monomethyl  ether, methyl cellosolve, ethyl cellosolve, ethylene glycol  tertiary butyl ether, tetrahydrofuran, 1,4-dioxane, n-methyl- 2-pyrrolidone, triethylene glycol monomethyl ether, diethyl› ene glycol dimethyl ether, and diethylene glycol diethyl ether.  [0317]  From the viewpoint of compatibility with the plat› ing catalyst or the precursor thereof, or organic solvent per› meability of the layer to be plated, acetone, dimethyl carbon› ate, dimethyl cellosolve, triethylene glycol monomethyl  ether, diethylene glycol dimethyl ether and diethylene glycol  diethyl ether are particularly preferred. 