JP4505260B2 - Metal pattern forming method - Google Patents

Description

  The present invention relates to a metal pattern forming method having a metal film in a pattern, and more particularly to a metal pattern forming method useful as a metal wiring board and a printed wiring board (FPC, TAB).

  Metal patterns formed on flexible substrates are used in various electrical appliances. In general, a substrate used in a product includes not only a metal pattern but also an IC chip and the like, which are connected to each other. As a method of connecting a metal pattern as wiring and a member such as an IC chip, (1) wire bonding connection in which a pad of an IC chip and a pad of a printed wiring board are connected by a fine wire of gold or aluminum, (2) On the flexible printed wiring board (hereinafter referred to as FPC as appropriate), a wiring for connecting the chip and the substrate is formed, and the chip is mounted on the wiring, and the TAB connection is connected to the substrate. (3) Connection bumps to the chip There is a flip-chip connection that connects to the substrate with this bump.

As a method for forming a metal pattern on such a substrate, the “subtractive method”, the “semi-additive method”, and the “full additive method” are mainly known. "Semi-additive method" is mainly used.
In the “subtractive method”, a metal layer formed on a substrate is provided with a photosensitive layer that is exposed to actinic rays, and this resist layer is imagewise exposed and developed to form a resist image. In this method, the metal is etched to form a metal pattern, and finally the resist is peeled off. In this method, the metal substrate used is roughened by treating the substrate with chromic acid or the like in order to provide adhesion between the substrate and the metal layer. For this reason, the metal component embedded in the recesses remains without being removed in the etching process, and there is a problem in the insulation between lines.
As a technology to form a highly adhesive metal film without roughening the surface of the substrate with chromic acid, etc., a metal with excellent adhesion can be obtained by grafting a radically polymerizable compound onto the substrate surface and modifying the surface. A method for easily forming a film has been proposed (see, for example, Patent Document 1, Non-Patent Documents 1 and 2). However, in reality, the metal component removability in the etching process of these metal films has not yet been studied.

In the “semi-additive method” which is another metal pattern forming method, a base substrate layer such as Cr is thinly formed on a substrate by plating or the like, and a resist pattern is formed on the base metal layer. Subsequently, after forming a metal layer such as Cu on the base metal layer in a region other than the resist pattern by plating, a wiring pattern is formed by removing the resist pattern. Further, the metal pattern is formed in a region other than the resist pattern by etching the base metal layer using the wiring pattern as a mask. This method also has the same problems as the subtractive method because the substrate is processed with chromic acid to make it adherent between the substrate and the metal layer, resulting in a new metal pattern formation method. Although it is desired, it has not yet been provided.
JP 58-196238 A “Advanced Materials”, 2000, No. 20, p. 1481-1494 N. Inagaki, S. Tasaka, M. Masumoto, “Macromolecules”, Vol. 29, P1624-1648

  The object of the present invention made in consideration of the above-mentioned conventional technical problems is that when forming a metal pattern by etching, the metal pattern non-formed part is excellent in removability by etching, and the formed metal pattern is adhered. An object of the present invention is to provide a method for forming a metal pattern having good properties.

As a result of intensive studies, the inventors have etched the metal film formed on the graft substrate, so that the metal components present at the substrate interface of the metal film can be easily removed. The present invention has been completed by finding that a metal pattern having excellent properties and adhesion can be formed.
That is, the metal pattern forming method of the present invention includes (a) a step of forming a graft polymer directly bonded to the surface of the substrate on the substrate, and (b) a step of forming a metal film on the graft polymer. (C) etching the metal film.

Here, as the step (a), a polymerization initiating layer is formed by immobilizing a polymer having a functional group having a polymerization initiating ability on a side chain and a polymer having a crosslinkable group by a crosslinking reaction on the substrate (a- 1 ). forming a graft polymer having (a-2) directly with the polymerization initiation layer surface throughout the polymerization initiation layer surface on the substrate bound and electroless plating catalyst or a precursor thereof that interact with the functional groups And the step (b) includes (b-1) applying an electroless plating catalyst or a precursor thereof to the graft polymer, and (b-2) electroless. And a step of performing plating.

  Although the action of the present invention is not clear, in the present invention, since the metal film is formed on the entire surface through the graft polymer layer chemically bonded to the substrate, it has excellent adhesion to the substrate, Since the substrate interface is not roughened, not only is the removability of the conductive component near the substrate interface good, but the graft polymer introduced on the base material is bonded to the base material at the end of the polymer chain, Since it has a structure with very high mobility and the etching solution can easily diffuse into the graft film during etching, it is considered that the conductive component on the surface of the substrate can be easily removed.

  According to the metal pattern forming method of the present invention, when forming a metal pattern by etching, it is easy to form a metal pattern that is excellent in removability by etching of a metal pattern non-formed part and has good adhesion of the formed metal pattern. Can be formed.

Hereinafter, the metal pattern forming method of the present invention will be described in detail.
Metal pattern of the present invention, on the (a) substrate, to form a polymerization initiation layer which is obtained by fixing, by cross-linking reaction, a polymer having a functional group and crosslinking group having polymerization initiation ability in the side chain, the polymerization initiator Forming a graft polymer directly bonded to the surface of the layer ; (b) forming a metal film on the graft polymer; and (c) etching the metal film.
First, [on that (a) forming a polymerization initiation layer which is obtained by fixing, by cross-linking reaction, a polymer having a functional group and crosslinking group having polymerization initiation ability in the side chain, directly to the polymerization initiating layer surface Step of forming a bonded graft polymer] will be described.
The step (a) is a step of introducing a graft polymer onto the surface of the substrate (surface graft forming method), and the graft polymer is a functional group that interacts with the electroless plating catalyst or its precursor, that is, a conductive material. Is a graft polymer having a functional group for imparting.

(Surface graft formation method)
The surface graft forming method applicable to the present invention uses a general means called surface graft polymerization.
Graft polymerization is a method in which an active species is provided on a polymer compound chain, whereby another monomer that initiates polymerization is further polymerized to synthesize a graft (grafting) polymer. When the compound forms a solid surface, it is called surface graft polymerization.

<Process to give active species to solid surface>
In the present invention, an active species is given to the surface of the substrate, and a graft polymer is generated using it as a base point. Specific examples of this method include the following methods.
A method of providing a polymerization initiation layer formed by immobilizing a polymer having a functional group having a polymerization initiating ability on a side chain and a polymer having a crosslinkable group by a crosslinking reaction on a substrate, and applying energy to generate active species on a solid surface ( This corresponds to the step (a- 1 )).

(Energy application method)
As a method for imparting energy to the surface of the polymerization initiation layer , for example, radiation irradiation such as heating or exposure can be used. For example, light irradiation with a UV lamp, visible light, or the like, heating with a hot plate, or the like is possible. Examples of the light source include a mercury lamp, a metal halide lamp, a xenon lamp, a chemical lamp, and a carbon arc lamp. Further, g-line, i-line, and Deep-UV light are also used. The time required for energy application varies depending on the amount of the target graft polymer produced and the light source, but is usually between 10 seconds and 5 hours.

This method is a step of forming a polymerization initiating layer on a substrate by immobilizing a polymer having a functional group having a polymerization initiating ability in a side chain and a polymer having a crosslinkable group by a crosslinking reaction.

First, a polymer having a polymerization initiating group and a crosslinkable group used in this step (hereinafter, a specific polymerization initiating polymer as appropriate) will be described.
This specific polymerization initiating polymer is required to have a polymerization initiating group and a crosslinkable group in the polymer structure, and can be obtained by copolymerizing a monomer having a polymerization initiating group and a monomer having a crosslinkable group. .

(Monomer having a polymerization initiating group)
The monomer having a polymerization initiating group constituting the specific polymerization initiating polymer is preferably composed of a monomer having a radical, anionic, or cationic polymerizable group capable of being polymerized with a pendant structure having the following polymerization initiating ability. That is, this monomer has a structure in which a polymerizable group and a polymerization initiating group are both present in the molecule.
The structure having the ability to initiate polymerization includes (a) aromatic ketones, (b) onium salt compounds, (c) organic peroxides, (d) thio compounds, (e) hexaarylbiimidazole compounds, (f) Examples thereof include ketoxime ester compounds, (g) borate compounds, (h) azinium compounds, (i) active ester compounds, (j) compounds having a carbon halogen bond, and (k) pyridinium compounds. From the viewpoint of polymerization initiating ability, (a), (c) and (j) are preferred. Any of these compounds can be used in the above (a) to (k). Hereinafter, (a), (c), and (j) that are particularly preferable in the present invention will be described with specific examples, but the present invention is not limited thereto.

(A) Aromatic ketones In the present invention, (a) aromatic ketones preferable as a structure having a polymerization initiating ability include “RADIATION CURING IN POLYMER SCIENCE AND TECHNOLOGY” P. Fouassier, J. et al. F. Examples include compounds having a benzophenone skeleton or a thioxanthone skeleton described in Rabek (1993), p77-117. For example, the following compounds are mentioned.

(C) Organic peroxide In the present invention, the organic peroxide (c) preferable as a structure having a polymerization initiating ability includes almost all organic compounds having one or more oxygen-oxygen bonds in the molecule. Examples include methyl ethyl ketone peroxide, cyclohexanone peroxide, acetylacetone peroxide, 1,1,3,3-tetramethylbutyl hydroperoxide, ditertiary butyl peroxide, tertiary butyl peroxylaurate, and tertiary butyl peroxide. Oxycarbonate, 3,3′4,4′-tetra- (t-butylperoxycarbonyl) benzophenone, 3,3′4,4′-tetra- (t-amylperoxycarbonyl) benzophenone, 3,3′4 , 4'-tetra- (t-hexylperoxycarbonyl) benzophenone, 3,3'4,4'-tetra- (t-octylperoxycarbonyl) benzophenone, 3,3'4,4'-tetra- (kumi Luperoxycarbonyl) benzophenone, 3,3'4 4'-tetra - (p-isopropyl cumylperoxycarbonyl) benzophenone, carbonyl di (t-butylperoxy) and carbonyl di (t-hexyl peroxy dihydrogen diphthalate), and the like.

(J) Compound having carbon halogen bond In the present invention, (j) a compound having a carbon halogen bond, which is preferable as a structure having a polymerization initiating ability, includes compounds described in the following general formulas (1) and (2). be able to.

In General Formula (1), X ¹ represents a halogen atom, and Y ¹ represents —C (X ¹ ) ₃ , —NH ₂ , —NHR ² , —NR ² , —OR ² . Here, R ¹¹ represents an alkyl group, a substituted alkyl group, an aryl group, or a substituted aryl group. R ¹ represents —C (X ¹ ) ₃ , an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, or a substituted alkenyl group.

In general formula (2), R ³ represents an alkyl group, a substituted alkyl group, an alkenyl group, a substituted alkenyl group, an aryl group, a substituted aryl group, a halogen atom, an alkoxy group, a substituted alkoxyl group, a nitro group, or a cyano group. . X ² represents a halogen atom. n represents an integer of 1 to 3.

  Specific examples of the compounds represented by the general formulas (1) and (2) include the following compounds.

  Among these structures having polymerization initiating ability, aromatic ketones and triazines having the following structure are preferably pendant to the polymerizable group. Moreover, as a preferable aromatic ketone, commercial items, such as Irgacure 184, can also be used.

  Moreover, as for the structure which has such a polymerization initiating ability, only 1 type may be pendant to the polymeric group, and 2 or more types may be pendant.

  Examples of the polymerizable group pendant with such a structure having a polymerization initiating ability include a polymerizable group capable of undergoing radical, anionic, and cationic polymerization such as an acryl group, a methacryl group, an acrylamide group, a methacrylamide group, and a vinyl group. Among these, an acrylic group and a methacryl group are particularly preferable from the viewpoint of ease of synthesis.

  Specific examples of the monomer having a polymerization initiating group in the present invention include monomers having the following structures.

Hereinafter, the monomer having a crosslinkable group will be described.
(Monomer having a crosslinkable group)
As the monomer having a crosslinkable group constituting the specific polymerization initiating polymer in the present invention, for example, a conventionally known crosslinkable group (structure used for the crosslink reaction as described in Shinji Yamashita “Crosslinker Handbook”). It is preferably a monomer comprising a radical, anion, or cationic polymerizable group having a pendant functional group). That is, this monomer has a structure in which a polymerizable group and a crosslinkable group are both present in the molecule.

Among these conventionally known crosslinkable groups, a carboxylic acid group (—COOH), a hydroxyl group (—OH), an amino group (—NH ₂ ), and an isocyanate group (—NCO) are preferably pendant to a polymerizable group. .
Moreover, as for such a crosslinkable group, only 1 type may be pendant by the polymeric group, and 2 or more types may be pendant.

  Examples of the polymerizable group pendant with these crosslinkable groups include polymerizable groups capable of polymerizing radicals, anions, and cationic groups such as acrylic groups, methacrylic groups, acrylamide groups, methacrylamide groups, and vinyl groups. Among these, an acrylic group and a methacryl group are particularly preferable from the viewpoint of ease of synthesis.

  Specific examples of the monomer having a crosslinkable group in the present invention include monomers having the following structures.

  In the specific polymerization initiating polymer in the present invention, the copolymerization molar ratio of the copolymerization component (A) having a polymerization initiating group and the copolymerization component (B) having a crosslinkable group is (A) 1-40. It is preferable that the mol% and (B) is 20 to 70 mol%. From the viewpoint of the film properties of the polymerization initiation layer after the graft polymerization reaction or the crosslinking reaction, it is more preferable that (A) is 5 to 30 mol% and (B) 30 to 60 mol%.

[Other copolymerization components (monomers)]
For the specific polymerization initiating polymer in the present invention, a third copolymerization component (monomer) as shown below is used in order to adjust the film forming property, hydrophilicity / hydrophobicity, solvent solubility, polymerization initiating property, etc. Also good.
As the third copolymer component, any compound can be used as long as it is a radical, anion, or cationic polymerizable compound. In view of polymerizability and the like, an acrylic or methacrylic monomer in which an alkyl group having 1 to 20 carbon atoms is pendant is preferable. At this time, the alkyl group is preferably an alkyl group having tertiary hydrogen in order to generate more active species by UV exposure. The alkyl group may be substituted with any substituent, but from the viewpoint of preventing the monomer solution from penetrating into the polymerization initiation layer, the alkyl group may be substituted with a substituent having a quaternary ammonium salt structure. preferable.

  A specific polymerization initiating polymer having a preferred structure can be synthesized by appropriately copolymerizing these monomers. In addition, any polymerization method can be used to synthesize the copolymer, but from the viewpoint of simplicity of the polymerization reaction, it is preferable to use a radical polymerization reaction. In this case, the radical generator for causing radical polymerization reaction is preferably a compound that generates a radical by heat.

  Further, the specific polymerization initiating polymer having this preferable structure is not limited to being synthesized by copolymerization as described above. For example, a polymer having a polymerization initiating group in the side chain is synthesized, and then You may synthesize | combine by introduce | transducing an appropriate amount of crosslinkable groups in a polymer. Alternatively, a specific polymerization initiating polymer may be synthesized by polymerizing one monomer unit having both a polymerization initiating group and a crosslinkable group.

  In consideration of the availability of the monomer, etc., the specific polymerization initiating polymer having a preferable structure is a mode in which a polymerization initiating group and a crosslinkable group are copolymerized and synthesized in different monomer units. It is preferable that

  The specific polymerization initiating polymer in the present invention can be synthesized by polymerizing the above-described monomers. In addition, any polymerization method can be used for the synthesis, but it is preferable to use a radical polymerization reaction from the viewpoint of simplicity of the polymerization reaction. In this case, the radical generator for causing radical polymerization reaction is preferably a compound that generates a radical by heat.

  The weight average molecular weight of the specific polymerization initiating polymer in the present invention is preferably 10,000 to 10,000,000, more preferably 10,000 to 5,000,000, and further preferably 100,000 to 1,000,000. When the weight average molecular weight of the specific polymerization initiating polymer in the present invention is less than 10,000, the polymerization initiating layer may be easily dissolved in the monomer solution.

[Polymerization initiation layer formed by immobilizing a specific polymerization initiation polymer by a crosslinking reaction]
In the polymerization initiation layer forming step, as a method for fixing the specific polymerization initiating polymer by a crosslinking reaction, there are a method using a self-condensation reaction of the specific polymerization initiating polymer and a method using a crosslinking agent in combination, and a crosslinking agent is used. Is preferred. The way to use the self-condensation reaction of the specific polymerization initiator polymer, for example, when the crosslinkable group is -NCO, in which self-condensation reaction using a property that proceeds by the application of heat. As this self-condensation reaction proceeds, a crosslinked structure can be formed.

Moreover, as a crosslinking agent used for the method of using a crosslinking agent together, a conventionally well-known thing as described in Shinji Yamashita "crosslinking agent handbook" can be used.
Preferred combinations of the crosslinkable group and the crosslinker in the specific polymerization initiating polymer include (crosslinkable group, crosslinker) = (— COOH, polyvalent amine), (—COOH, polyvalent aziridine), (—COOH, Polyvalent isocyanate), (—COOH, polyvalent epoxy), (—NH ₂ , polyvalent isocyanate), (—NH ₂ , aldehydes), (—NCO, polyvalent amine), (—NCO, polyvalent isocyanate) , (—NCO, polyhydric alcohol), (—NCO, polyhydric epoxy), (—OH, polyhydric alcohol), (—OH, polyhalogenated compound), (—OH, polyhydric amine), (− OH, acid anhydride). Among these, (functional group, cross-linking agent) = (— OH, polyvalent isocyanate) is a more preferable combination in that a urethane bond is formed after the cross-linking and a high-strength cross-linking can be formed.
Specific examples of the crosslinking agent in the present invention include the structures shown below.

  Such a crosslinking agent is added to the coating solution containing the above-mentioned specific polymerization initiating polymer when the polymerization initiating layer is formed. Thereafter, the crosslinking reaction proceeds by the heat during the drying of the coating film, and a strong crosslinked structure can be formed. More specifically, the following ex1. Or the dehydration reaction indicated by ex2. The cross-linking reaction proceeds by the addition reaction represented by the above, and a cross-linked structure is formed. The temperature conditions in these reactions are preferably 50 ° C. or higher and 300 ° C. or lower, more preferably 80 ° C. or higher and 200 ° C. or lower.

  The amount of the crosslinking agent added in the coating solution varies depending on the amount of the crosslinkable group introduced into the specific polymerization initiating polymer, but is usually 0.01 to 50 with respect to the number of moles of the crosslinkable group. It is preferably an equivalent, more preferably 0.01 to 10 equivalent, and still more preferably 0.5 to 3 equivalent. When the addition amount of the crosslinking agent is less than this upper limit value, the degree of crosslinking becomes low and the polymerization initiating layer is easily dissolved in the monomer solution. Further, when the amount of the crosslinking agent added is larger than the upper limit value, the unreacted crosslinking agent component may remain in the polymerization initiation layer and may elute into the monomer solution, thereby adversely affecting the polymerization reaction.

[Deposition of polymerization initiation layer]
In this step, the above-mentioned specific polymerization initiating polymer is dissolved in a suitable solvent, a coating solution is prepared, the coating solution is placed on the substrate by coating, the solvent is removed, and the crosslinking reaction proceeds. The film is formed by
In addition, when a specific polymerization initiating polymer synthesized only from a monomer having a polymerization initiating group is used when forming the polymerization initiating layer, it is not necessary for the crosslinking reaction to proceed. After the preparation, the coating solution may be disposed on the substrate by coating or the like, and the solvent may be removed (dried).

(solvent)
The solvent used when applying the polymerization initiation layer is not particularly limited as long as the above-mentioned specific polymerization initiation polymer is dissolved. From the viewpoint of easy drying and workability, a solvent having a boiling point that is not too high is preferable. Specifically, a solvent having a boiling point of about 40 ° C to 150 ° C may be selected.
Specifically, acetone, methyl ethyl ketone, cyclohexane, ethyl acetate, tetrahydrofuran, toluene, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, acetylacetone, cyclohexanone, methanol, Ethanol, 1-methoxy-2-propanol, 3-methoxypropanol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, - such as methoxypropyl acetate.
These solvents can be used alone or in combination. The concentration of the solid content in the coating solution is suitably 2 to 50% by mass.

The coating amount of the polymerization initiating layer is preferably 0.1 to 20 g / m ² in terms of weight after drying from the viewpoint of achieving sufficient expression of polymerization initiating ability and excellent film properties. 1-15 g / m < ² > is preferable.

[(A-2) Step of forming a graft polymer having a functional group directly bonded to the surface of the base material and interacting with the electroless plating catalyst or a precursor thereof over the entire surface of the base material]
A step of introducing a graft polymer having a functional group that interacts with the electroless plating catalyst or its precursor from the active site as a base point is performed on the base material obtained as described above. Hereinafter, this step, that is, the step (a-2) will be described.
In order to introduce a graft polymer having a functional group that interacts with an electroless plating catalyst or a precursor thereof onto a solid surface, a polymerizable group and a functional group that interacts with the electroless plating catalyst or a precursor thereof (hereinafter, It can be introduced by reacting a compound having an interactive group) with an active species generated on the solid surface.

(Compound having a polymerizable group and an interactive group)
The compound having a polymerizable group and an interactive group used in the present invention is a homopolymer obtained by using a monomer having an interactive group described later, or at least one selected from monomers having the interactive group , Refers to a polymer in which an ethylene addition polymerizable unsaturated group (polymerizable group) such as a vinyl group, an allyl group, or a (meth) acryl group is introduced into the copolymer as a polymerizable group. Have a polymerizable group.

<Example of monomer having interactive group>
Monomers that can be used include (meth) acrylic acid or alkali metal salts and amine salts thereof, itaconic acid or alkali metal salts and amine salts thereof, styrene sulfonate, 2-hydroxyethyl (meth) acrylate, and (meth) acrylamide. N-monomethylol (meth) acrylamide, N-dimethylol (meth) acrylamide, allylamine or its hydrohalide, 3-vinylpropionic acid or its alkali metal salt and amine salt, vinylsulfonic acid or its alkali metal salt, and Amine salt, 2-sulfoethyl (meth) acrylate, polyoxyethylene glycol mono (meth) acrylate, 2-acrylamido-2-methylpropanesulfonic acid, acid phosphooxypolyoxyethylene glycol mono ( ) Acrylate, N-vinylpyrrolidone (the following structure), sodium styrenesulfonate, vinylbenzoic acid, etc. can be used. Generally, carboxyl group, sulfonic acid group, phosphoric acid group, amino group or salts thereof, hydroxyl group , An amide group, a phosphine group, an imidazole group, a pyridine group, or a salt thereof, and a monomer having a functional group such as an ether group can be used.

<Polymer having polymerizable group and interactive group>
A polymer having a polymerizable group and an interactive group can be synthesized as follows.
As synthesis methods, i) a method in which a monomer having an interactive group and a monomer having a polymerizable group are copolymerized, and ii) a monomer having an interactive group and a monomer having a double bond precursor are copolymerized. And a method of introducing a double bond by treatment with a base or the like, and iii) a method of reacting a polymer having an interactive group with a monomer having a polymerizable group. From the viewpoint of synthesis suitability, iii) a method of introducing a polymerizable group by reacting a polymer having an interactive group with a monomer having a polymerizable group, and ii) a monomer having an interactive group And a monomer having a double bond precursor are copolymerized and then a double bond is introduced by treatment with a base or the like.

  In the above method iii), the monomer having an interactive group used for the synthesis of a polymer having a polymerizable group and an interactive group is (meth) acrylic acid or an alkali metal salt and amine salt thereof, itaconic acid. Or alkali metal salts and amine salts thereof, 2-hydroxyethyl (meth) acrylate, (meth) acrylamide, N-monomethylol (meth) acrylamide, N-dimethylol (meth) acrylamide, allylamine or a hydrohalide thereof, 3 -Vinyl propionic acid or its alkali metal salt and amine salt, vinyl sulfonic acid or its alkali metal salt and amine salt, 2-sulfoethyl (meth) acrylate, polyoxyethylene glycol mono (meth) acrylate, 2-acrylamido-2-methylpro Sulfonic acid, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, N-vinylpyrrolidone (the following structure) can be used, and in general, carboxyl group, sulfonic acid group, phosphoric acid group, amino group, or these And a monomer having a functional group such as a salt, a hydroxyl group, an amide group, a phosphine group, an imidazole group, a pyridine group, or a salt thereof, and an ether group.

Examples of the monomer having a polymerizable group that is copolymerized with the monomer having an interactive group include allyl (meth) acrylate and 2-allyloxyethyl methacrylate.
Monomer having a polymerizable group used for introducing an unsaturated group by reaction with a functional group such as a carboxyl group, an amino group or a salt thereof, a hydroxyl group and an epoxy group in a polymer having an interactive group As (meth) acrylic acid, glycidyl (meth) acrylate, allyl glycidyl ether, 2-isocyanatoethyl (meth) acrylate, and the like.

  Next, ii) a method of copolymerizing a monomer having an interactive group and a monomer having a double bond precursor and then introducing a double bond by treatment with a base or the like will be described in detail. Regarding this synthesis method, the method described in JP-A No. 2003-335814 can be used. As the monomer having a double bond precursor, compounds (i-1 to i-60) described in JP-A-2003-335814 can be used, and among these, the following (i-1) is particularly preferable.

-Base used for elimination reaction-
In the method ii), the base used for introducing a double bond by treatment with a base or the like is preferably an alkali metal hydride, hydroxide or carbonate, organic amine compound, or metal alkoxide compound. Take as an example.
Preferred examples of alkali metal hydrides, hydroxides or carbonates include sodium hydride, calcium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, calcium hydroxide, potassium carbonate, sodium carbonate, carbonate Examples include potassium hydrogen and sodium hydrogen carbonate.

  Preferable examples of the organic amine compound include trimethylamine, triethylamine, diethylmethylamine, tributylamine, triisobutylamine, trihexylamine, trioctylamine, N, N-dimethylcyclohexylamine, N, N-diethylcyclohexylamine, N- Methyldicyclohexylamine, N-ethyldicyclohexylamine, pyrrolidine, 1-methylpyrrolidine, 2,5-dimethylpyrrolidine, piperidine, 1-methylpiperidine, 2,2,6,6-tetramethylpiperidine, piperazine, 1,4-dimethyl Piperazine, quinuclidine, 1,4-diazabicyclo [2,2,2] -octane, hexamethylenetetramine, morpholine, 4-methylmorpholine, pyridine, picoline, 4-dimethylaminopyridine, Cytidine, 1,8-diazabicyclo [5,4,0] -7-undecene (DBU), N, N'-dicyclohexylcarbodiimide (DCC), diisopropylethylamine, Schiff base, and the like.

Preferable examples of the metal alkoxide compound include sodium methoxide, sodium ethoxide, potassium t-butoxide and the like. These bases may be used alone or in combination of two or more.
The amount of the base used may be equal to or less than the equivalent or greater than or equal to the amount of the specific functional group in the compound.
The temperature condition in the elimination reaction may be any of room temperature, cooling, and overheating. As preferable temperature conditions, it is the range of -20-100 degreeC.

As an example of a compound having a polymerizable group and an interactive group, a macromonomer can also be used.
As a method for producing the macromonomer used in this case, for example, Chapter 2 “Macromonomer” of “Macromonomer Chemistry and Industry” (editor Yuya Yamashita) published on September 20, 1999, published by IPC Publishing Bureau. Various production methods have been proposed in "Synthesis of". Particularly useful macromonomers that can be used include macromonomers derived from carboxyl group-containing monomers such as acrylic acid and methacrylic acid, 2-acrylamido-2-methylpropanesulfonic acid, vinylstyrene sulfonic acid, and salts thereof Sulfonic acid macromonomer derived from the above monomers, (meth) acrylamide, N-vinylacetamide, N-vinylformamide, amide macromonomer derived from N-vinylcarboxylic acid amide monomer, hydroxyethyl methacrylate, hydroxy Macromonomers derived from hydroxyl group-containing monomers such as ethyl acrylate and glycerol monomethacrylate, methoxyethyl acrylate, methoxypolyethylene glycol acrylate, polyethylene glycol acrylate DOO macromonomers derived from alkoxy group or ethylene oxide group-containing monomers such as. A monomer having a polyethylene glycol chain or a polypropylene glycol chain can also be usefully used as the macromonomer used in this embodiment.
In these macromonomers, a useful weight average molecular weight is in the range of 250 to 100,000, and a particularly preferable range is 400 to 30,000.

The solvent used in the composition containing the compound having a polymerizable group and an interactive group is not particularly limited as long as the compound having the polymerizable group and the interactive group as main components can be dissolved. Water-soluble solvents and organic solvents can be used. Further, a surfactant may be added to these solvents.
Examples of the solvent that can be used include alcohol solvents such as methanol, ethanol, propanol, ethylene glycol, glycerin, and propylene glycol monomethyl ether, acids such as acetic acid, ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone, formamide, and dimethylacetamide. Examples thereof include amide solvents.

  The surfactant that can be added to the solvent as needed may be any that dissolves in the solvent. Examples of such surfactants include an anionic surfactant such as sodium n-dodecylbenzenesulfonate. Agents, cationic surfactants such as n-dodecyltrimethylammonium chloride, polyoxyethylene nonylphenol ether (commercially available products such as Emulgen 910, manufactured by Kao Corporation), polyoxyethylene sorbitan monolaurate (commercially available) Examples of the product include a trade name “Tween 20” and the like, and nonionic surfactants such as polyoxyethylene lauryl ether.

When the graft polymer is produced by bringing the composition into contact with the substrate surface in a liquid state, it can be arbitrarily performed, but the coating amount when applying the composition to the substrate surface in the coating method is sufficient. from the viewpoint of obtaining a Do coating film is preferably 0.1 to 10 g / m ² in terms of solid content, especially 0.5 to 5 g / m ² preferably.
The formed graft membrane preferably has a thickness of 0.1 to 2.0 g / m ² , more preferably 0.3 to 1.0 g / m ² , and most preferably 0.5 to 1.0 g / m ^{2. 2} . In this range, the conductive material, metal ions, electroless plating catalyst, and precursors thereof, which will be described later, can be sufficiently adsorbed, and a metal film having preferable conductivity can be obtained, and the movement of the graft polymer chain It is possible to achieve excellent etching removability of the conductive component in the etching process due to high performance.

In grayed raft film forming technique, a polymerization initiation layer in only heating method for forming a polymerization initiation layer formed by immobilizing a polymer by cross-linking reaction, a polymer having a functional group and crosslinking group having polymerization initiation ability in the side chain formation can also good preferable in terms of generating active sites to active ray, for example, UV.

[(B) Step of forming metal film on graft polymer]
Next, the step of forming a metal film on the graft polymer obtained in the step (a) will be described.
In the present invention, the step of forming the metal film includes (b-1) a step of applying an electroless plating catalyst or a precursor thereof to the graft polymer prepared by the above method (hereinafter referred to as “electroless plating catalyst applying step” as appropriate). And (b-2) a step of performing electroless plating (hereinafter referred to as “electroless plating step” as appropriate).

[(B-2) Electroless plating catalyst application step]
In step (b), (b-1) an electroless plating catalyst or a precursor thereof is first applied to the graft polymer generated in the surface grafting step.
<Electroless plating catalyst>
The electroless plating catalyst used in this step is mainly a zero-valent metal, and examples thereof include Pd, Ag, Cu, Ni, Al, Fe, and Co. In the present invention, Pd and Ag are particularly preferable because of their good handleability and high catalytic ability. As a method for fixing the zero-valent metal to the interactive region, for example, a metal colloid whose charge is adjusted so as to interact with an interactive group on the interactive region is applied to the interactive region. A technique is used. In general, a metal colloid can be prepared by reducing metal ions in a solution containing a charged surfactant or a charged protective agent. The charge of the metal colloid can be adjusted by the surfactant or the protective agent used here, and the metal colloid whose charge is adjusted in this way interacts with the interactive group (polar group) of the graft polymer. By doing so, a metal colloid (electroless plating catalyst) can be attached to the graft polymer.

<Electroless plating catalyst precursor>
The electroless plating catalyst precursor used in this step can be used without particular limitation as long as it can become an electroless plating catalyst by a chemical reaction. Mainly, metal ions of zero-valent metal used in the electroless plating catalyst are used. The metal ion that is an electroless plating catalyst precursor becomes a zero-valent metal that is an electroless plating catalyst by a reduction reaction. The metal ion which is an electroless plating catalyst precursor is applied to the substrate in the step (b-1), and before being immersed in the electroless plating bath, the metal ion is changed to a zero-valent metal by a separate reduction reaction. A plating catalyst may be used, or the electroless plating catalyst precursor may be immersed in an electroless plating bath and changed to a metal (electroless plating catalyst) by a reducing agent in the electroless plating bath.

In practice, the metal ion that is the electroless plating precursor is imparted to the graft polymer in the form of a metal salt. The metal salt used is not particularly limited as long as it is dissolved in a suitable solvent and dissociated into a metal ion and a base (anion), and M (NO ₃ ) n, MCn, M _{2 / n} (SO ₄ ), M _{3 / n} (PO ₄ ) (M represents an n-valent metal atom), and the like. As a metal ion, the thing which said metal salt dissociated can be used suitably. Specific examples include, for example, Ag ions, Cu ions, Al ions, Ni ions, Co ions, Fe ions, and Pd ions, and Ag ions and Pd ions are preferable in terms of catalytic ability.

As a method of applying a metal colloid as an electroless plating catalyst or a metal salt as an electroless plating precursor to a graft polymer, the metal colloid is dispersed in an appropriate dispersion medium, or the metal salt is dissolved in an appropriate solvent. Then, a solution containing dissociated metal ions is prepared, and the solution is applied to the surface of the substrate on which the graft polymer is present, or the substrate having the graft polymer is immersed in the solution. By contacting a solution containing a metal ion, a metal ion is attached to an interactive group of the graft polymer by using an ion-ion interaction or a dipole-ion interaction. The active region can be impregnated with metal ions.
From the viewpoint of sufficiently performing such adhesion or impregnation, the metal ion concentration or the metal salt concentration in the solution to be contacted is preferably in the range of 0.01 to 50% by mass, preferably 0.1 to 30%. More preferably, it is in the range of mass%. Further, the contact time is preferably about 1 minute to 24 hours, more preferably about 5 minutes to 1 hour.

[(B-2) Electroless plating step]
In the step (b-2), a conductive film (metal film) is formed by performing electroless plating on the base material to which the electroless plating catalyst or the like is applied from the electroless plating catalyst or the like application step. The That is, by performing electroless plating in this step, a high-density conductive film (metal film) is formed on the graft polymer obtained in the above step. The formed conductive film (metal film) has excellent conductivity and adhesion.

<Electroless plating>
Electroless plating refers to an operation of depositing a metal by a chemical reaction using a solution in which metal ions to be deposited as a plating are dissolved.
In the electroless plating in this step, for example, the substrate provided with the electroless plating catalyst obtained in the electroless plating catalyst application step is washed with water to remove excess electroless plating catalyst (metal). Thereafter, it is immersed in an electroless plating bath. As the electroless plating bath to be used, a generally known electroless plating bath can be used.
In addition, when the base material to which the electroless plating catalyst precursor is applied is immersed in the electroless plating bath in a state where the electroless plating catalyst precursor is attached to or impregnated with the graft polymer, the base material is washed with water to remove excess. After removing a precursor (such as a metal salt), it is immersed in an electroless plating bath. In this case, reduction of the precursor and subsequent electroless plating are performed in the electroless plating bath. As the electroless plating bath used here, a generally known electroless plating bath can be used as described above.

The composition of a general electroless plating bath is as follows: 1. metal ions for plating, 2. reducing agent; Additives (stabilizers) that improve the stability of metal ions are mainly included. In addition to these, the plating bath may contain known additives such as a plating bath stabilizer.
As the types of metals used in the electroless plating bath, copper, tin, lead, nickel, gold, palladium, and rhodium are known, and among these, copper and gold are particularly preferable from the viewpoint of conductivity.
In addition, there are optimum reducing agents and additives according to the above metals. For example, a copper electroless plating bath contains Cu (SO ₄ ) ₂ as a copper salt, HCOH as a reducing agent, and a chelating agent such as EDTA or Rochelle salt as a copper ion stabilizer as an additive. The plating bath used for electroless plating of CoNiP includes cobalt sulfate and nickel sulfate as metal salts, sodium hypophosphite as a reducing agent, sodium malonate, sodium malate and sodium succinate as complexing agents. It is included. Further, the electroless plating bath of palladium contains (Pd (NH ₃ ) ₄ ) Cl ₂ as metal ions, NH ₃ and H ₂ NNH ₂ as reducing agents, and EDTA as a stabilizer. These plating baths may contain components other than the above components.

  The film thickness of the conductive film (metal film) thus formed can be controlled by the concentration of the metal salt or metal ion in the plating bath, the immersion time in the plating bath, the temperature of the plating bath, or the like. From the viewpoint of conductivity, it is preferably 0.5 μm or more, and more preferably 3 μm or more. Further, the immersion time in the plating bath is preferably about 1 minute to 3 hours, and more preferably about 1 minute to 1 hour.

[Electroplating process]
In this aspect, (b-3) an electroplating step (electroplating step) may be provided after the (b-2) electroless plating step. In this step, after the electroless plating in the electroless plating step, electroplating can be performed using the metal film formed in this step as an electrode. As a result, a metal film having an arbitrary thickness can be easily formed on the basis of the metal film having excellent adhesion to the substrate. By adding this step, the metal pattern can be formed with a thickness according to the purpose, and the conductive material obtained by this aspect is suitable for application to various applications.

  As the electroplating method in this embodiment, a conventionally known method can be used. In addition, as a metal used for the electroplating of this process, copper, chromium, lead, nickel, gold, silver, tin, zinc, etc. are mentioned. From the viewpoint of conductivity, copper, gold, and silver are preferable. More preferred.

  The film thickness of the metal film obtained by electroplating differs depending on the application, and can be controlled by adjusting the concentration of metal contained in the plating bath, the dipping time, or the current density. In addition, from the viewpoint of conductivity, the film thickness when used for general electric wiring or the like is preferably 0.3 μm or more, and more preferably 3 μm or more.

In the metal film obtained as described above, the surface of the substrate is surface-grafted, and when the electroless plating catalyst or precursor thereof is allowed to act on the surface graft layer and electroless plating is performed, the surface graft polymer chain becomes the substrate. Since it is formed by polymerization from the interface, its mobility is high and it is easy to act on the electroless plating catalyst or its precursor. In addition, due to its high mobility, the electroless plating solution easily penetrates into the film, and the electroless plating proceeds inside or on the surface graft layer. As a result, the substrate interface of the metal film portion was in a hybrid state with the polymer directly bonded to the substrate, and thus the adhesion was good.
Next, a method for forming a metal pattern by etching a metal film formed over the entire surface of the substrate will be described.

(C) Step of etching the metal film to form a metal pattern]
“Subtractive method” and “semi-additive method” are used as etching methods in the method of forming a metal pattern by etching the metal film obtained by the present invention.

"Subtractive method"
The subtractive method is: (1) Applying a resist layer on the metal film created by the above method → (2) Forming resist pattern of conductor to be left by pattern exposure and development → (3) Unnecessary metal by etching Remove film → (4) A method of peeling a resist layer and forming a metal pattern. The thickness of the metal film used in this embodiment is preferably 5 μm or more, and more preferably in the range of 5 to 30 μm.

(1) Resist layer coating step resist As the photosensitive resist to be used, a photocurable negative resist or a photodissolvable positive resist that dissolves upon exposure can be used. As the photosensitive resist, 1. photosensitive dry film resist (DFR); 2. liquid resist; An ED (electrodeposition) resist can be used. Each of these has its own characteristics. 1. A photosensitive dry film resist (DFR) can be used in a dry manner, so that it is easy to handle. Since the liquid resist can have a thin film thickness as a resist, a pattern with good resolution can be formed. 3. Since an ED (electrodeposition) resist can have a thin film thickness as a resist, it can form a pattern with good resolution, has good follow-up to unevenness on the coated surface, and has excellent adhesion. The resist to be used may be appropriately selected in consideration of these characteristics.

Application method 1. Photosensitive dry film The photosensitive dry film generally has a sandwich structure sandwiched between a polyester film and a polyethylene film, and is pressed with a hot roll while peeling the polyethylene film with a laminator.
2. Liquid resist coating methods include spray coating, roll coating, curtain coating, and dip coating. In order to apply both surfaces simultaneously, roll coating and dip coating are preferable because both surfaces can be coated simultaneously.

3. ED (Electrodeposition) Resist ED resist is a colloid obtained by suspending a photosensitive resist in fine particles and suspending in water. Since the particles are charged, when a voltage is applied to the conductor layer, A resist can be deposited on the conductor layer, and the colloid can be coated on the conductor to form a film.

(2) Pattern exposure process "Exposure"
A base material provided with a resist film on the upper part of the metal film is brought into close contact with a mask film or a dry plate, and exposed to light in a photosensitive region of the resist used. In the case of using a film, the film is exposed with a vacuum printing frame. Regarding the exposure source, a point light source can be used when the pattern width is about 100 μm. When forming a pattern having a pattern width of 100 μm or less, it is preferable to use a parallel light source.
"developing"
Any photo-curing negative resist can be used as long as it can dissolve the unexposed area, or a photo-dissolving positive resist that dissolves upon exposure, so long as it can dissolve the exposed area. An aqueous solution is used. In recent years, an alkaline aqueous solution has been used in order to reduce environmental burden.

(3) Etching process "Etching"
Etching is a process for forming a conductor pattern by chemically dissolving an exposed metal layer without a resist. The etching process is mainly performed by a horizontal conveyor device by spraying an etching solution from above and below. As the etchant, the metal layer is oxidized and dissolved with an oxidizing aqueous solution. Examples of etching solutions include ferric chloride solution, cupric chloride solution, and alkali etchant. Since the resist may be peeled off by alkali, a ferric chloride solution and a cupric chloride solution are mainly used.
In the method of the present invention, since the substrate interface is not roughened, the conductive polymer in the vicinity of the substrate interface has good removability, and the graft polymer in which the metal film is introduced onto the base material is a polymer chain. In this etching process, the etchant can easily diffuse into the graft polymer layer because it is bonded to the substrate at the end and has a very high mobility structure, and the interface between the substrate and the metal layer. Since the metal component is easily removed from the portion, it is possible to form a pattern with excellent sharpness.

(4) Resist peeling process “Peeling process”
After the metal (conductive) pattern is completed by etching, the etching resist that is no longer needed is no longer needed, and a process of peeling it off is necessary. Peeling can be performed by spraying a stripping solution. The stripping solution varies depending on the type of resist, but generally, a solvent or solution that swells the resist is wiped with a spray, and the resist is swollen and stripped.

(Regarding other processes)
Furthermore, in order to use as electric wiring, the following processes may be performed as needed.
"Drilling process"
In recent years, it has been required to form many electrical wirings on a single substrate, as well as thinning the metal pattern, forming electrical wiring on the front and back of the substrate, drilling holes in the substrate as necessary, A method is used in which conductive treatment is performed to increase the number of electrical wirings per substrate. The drilling process used here is mainly performed by an NC (Numerical control) drilling device.

"Desmear process"
In the drilling process, considerable heat is generated in a short time due to friction between the drill and the hole wall, the temperature in the hole rises, and resin smear occurs. Resin smear adversely affects the process of plating holes (through-hole plating process). Therefore, it is necessary to remove this smear, and this process is called a desmear process. In general desmear process, after treatment with a conditioner that swells the resin, the resin is treated with an alkaline permanganate (permanganate 40-80 g / L, temperature 50-80 ° C., time 5-20 minutes). Is oxidized and dissolved to remove smear.

"Hole Conduction Process (Through Hole Formation Process)"
In this invention, you may have the process (electroconductive process process) which performs an electroconductive process to the hole formed by the said process after the above-mentioned drilling process. In addition, this process may be performed independently from the above-described other processes, and other processes (such as the electroless plating process) may also serve as this process.
Conduction of the hole formed by the above-described drilling step in the conductive treatment step is performed by embedding a conductive material inside the hole. Specific examples of the conductive material include copper, nickel, chromium, titanium, aluminum, molybdenum, tungsten, zinc, tin, indium, gold, silver, and the like, or alloys thereof (such as nichrome). ); Conductive polymer materials such as polypyrrole and polythiophene; non-metallic inorganic conductive materials such as graphite and conductive ceramics; and the like.

Examples of the method for embedding the conductive material in the hole include an electroless plating method or a coating method. The reason for this is that the electroless plating method and the coating method enable relatively uniform and easy conductivity formation in a minute space such as the inner surface of the hole.
Specifically, for example, when conducting a conductive treatment by embedding a metal material in the hole, a chemical metal plating method (electroless plating method) is particularly preferably performed by applying a catalyst to the inside of the hole. . This electroless plating is conveniently performed simultaneously with the electroless plating process on the graft polymer in the above-described electroless plating step.

  Further, in the case where the inside of the hole is filled with a conductive polymer material for conducting the conductive treatment, an electroless plating method or a coating method is employed. In the electroless plating method, an appropriate oxidizing agent is applied to the inside of the hole, and then the substrate is immersed in a solution containing pyrrole or thiophene monomer, for example, a pyrrole solution. In the application method, a solution obtained by dissolving a conductive polymer such as polypyrrole or poly 1,4 dioxythiophene in a solvent may be used, and this solution may be applied on the graft layer and the hole provided on the substrate.

  In addition, in the case where the inside of the hole is filled with a non-metallic inorganic conductive material such as graphite and the conductive treatment is performed, an electroless plating method using no catalyst is suitably employed. In the case of using graphite plating as an example, the surface of the hole is treated with a pretreatment liquid, and then the laminate is immersed in the graphite dispersion. A representative example of the graphite plating solution that can be used in this process is Direct Plating (registered trademark), which is a graphite plating solution manufactured by MEC. This graphite plating solution is a set of a pretreatment liquid (MEC S process SP-6560) and a graphite dispersion liquid (MEC S process SP-6601).

"Application of solder resist"
The solder resist is a resin layer newly formed on the completed conductor pattern, and is for preventing solder adhesion. 2. maintaining insulation between conductors; 3. protection of conductors; 4. improvement of electrical characteristics; It is formed for the purpose of a mold base of a package such as BGA.

"surface treatment"
When various electronic components (such as IC chips) are mounted on a printed wiring board, it is necessary to surface-treat the connection portion. When soldering, 1A. HASL (solder coat), 1B. Precipitation solder coating, 1C. Preflux treatment. Connection parts such as wire bonding and print contact parts are 2A. Nickel / gold plating is performed.

1A. HASL
It is coating by dipping, and is an operation performed to protect the surface where the conductor substrate of the conductor pattern is exposed and to improve the solderability when mounting components. First, in order to improve the adhesion of the solder, a flux is applied, immersed in molten solder, and when pulled up, high-temperature and high-pressure air is sprayed from the nozzle onto the panel to remove excess solder.

1B. Precipitation type solder coat A method using a fine powder of tin, organic acid lead and rosin paste applied to the entire surface, and a chemical reaction occurs when heated to 183 ° C or higher to selectively deposit tin / lead alloy on the conductor. .
1C. Preflux A pre-flux process that protects the exposed conductor surface and provides good solder wettability during soldering. Preflux is compatible with the flux used when soldering parts and is used to protect the conductor surface before use from oxidation.

2A. Nickel / gold plating Nickel plating and gold plating. Generally, nickel plating is deposited at about 2 μm, and soft gold plating is deposited thereon at 0.05 to 0.8 μm. As the gold plating, displacement plating and electroless plating can be used.

"Semi-additive method"
The semi-additive method is: (1) application of a resist layer on a metal film formed on a graft polymer → (2) formation of a resist pattern of a conductor to be removed by pattern exposure and development → (3) resist path formation by plating Forming a metal film in a non-pattern part → (4) Stripping DFR → (5) A metal pattern forming method of removing an unnecessary metal film by etching. In these steps, the same technique as the “subtractive method” can be used. As the plating method, electroless plating or electroplating described above can be used. In addition, the thickness of the metal film used is preferably about 1 to 3 μm in order to complete the etching process in a short time. Moreover, you may perform electrolytic plating and electroless plating further with respect to the formed metal pattern.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these.
[Synthesis Example 1]
(Synthesis of specific polymerization initiating polymer A)
30 g of propylene glycol monomethyl ether (MFG) was added to a 300 ml three-necked flask and heated to 75 degrees. There, 8.1 g of [2- (acryloyloxy) ethyl] (4-benzoylbenzyl) dimethylammonium bromide, 9.9 g of 2-hydroxyethyl methacrylate, 13.5 g of isopropyl methacrylate, dimethyl-2,2′-azobis A solution of (2-methylpropionate) 0.43 g and MFG 30 g was added dropwise over 2.5 hours. Thereafter, the reaction temperature was raised to 80 ° C., and the reaction was further continued for 2 hours to obtain the following specific polymerization initiating polymer A.

[Synthesis Example 2]
(Synthesis of specific polymerization initiating polymer B)
30 g of propylene glycol monomethyl ether (MFG) was added to a 300 ml three-necked flask and heated to 75 degrees. There, 5.1 g of 4-methacryloyloxy-benzophenone, 9.9 g of 2-hydroxyethyl methacrylate, 9.8 g of isopropyl methacrylate, 3.97 g of [2- (methacryloyloxy) ethyl] trimethylammonium bromide, A solution of 0.43 g of dimethyl-2,2′-azobis (2-methylpropionate) and 30 g of propylene glycol monomethyl ether (MFG) was added dropwise over 2.5 hours. Thereafter, the reaction temperature was raised to 80 ° C., and the reaction was further continued for 2 hours to obtain the following specific polymerization initiating polymer B.

[Example 1]
[Formation of metal film]
A polyimide film (product name: Kapton, manufactured by Toray DuPont) was used as a substrate, and the following polymerization initiation layer coating solution 1 was applied to the surface using a rod bar No. 18, and dried and crosslinked at 110 ° C. for 10 minutes. . The film thickness of the obtained polymerization initiation layer was 8.9 μm.

<Polymerization initiation layer coating solution 2>
・ 0.4 g of the specific polymerization initiation polymer A
・ TDI (Tolylene-2,4-diisocyanate) 0.16g
・ Methyl ethyl ketone (MEK) 1.6g

[Grafting process]
The polyimide film on which the polymerization initiating layer is formed is immersed in an aqueous solution containing acrylic acid (10% by mass) and sodium periodate (NaIO4, 0.01% by mass), and the above 1.5 kW is added under an argon atmosphere. Using a high-pressure mercury lamp, light was irradiated for 10 minutes. After the light irradiation, the obtained film was thoroughly washed with ion exchange water to obtain a substrate 1 grafted with acrylic acid on the substrate.

[Plating process]
The graft substrate 1 was immersed in a 0.1% by mass aqueous solution of palladium nitrate (manufactured by Wako Pure Chemical Industries, Ltd.) for 1 hour, and then washed with distilled water. Thereafter, electroless plating was performed for 10 minutes in an electroless plating bath having the following composition.
<Electroless plating bath components>
・ OPC Kappa-H T1 (Okuno Pharmaceutical Co., Ltd.) 6mL
・ OPC Kappa-H T2 (Okuno Pharmaceutical Co., Ltd.) 1.2mL
・ OPC Kappa-H T3 (Okuno Pharmaceutical Co., Ltd.) 10mL
・ Water 83mL

Furthermore, the metal film 1 was produced by electroplating for 15 minutes in an electroplating bath having the following composition.
<Composition of electroplating bath>
・ Copper sulfate 38g
・ 95 g of sulfuric acid
・ Hydrochloric acid 1mL
・ Copper Greeme PCM (Meltex Co., Ltd.) 3mL
・ Water 500g

(Etching process)
A photosensitive dry film (manufactured by Fuji Photo Film) is laminated on the obtained metal film 1 and passed through a mask film on which a desired conductor circuit pattern is drawn (a metal pattern portion is an opening portion and a metal pattern non-forming portion is a mask portion). After exposing to ultraviolet rays, printing an image, developing, removing copper in the non-metal part of the metal pattern using a cupric chloride etchant, the dry film was peeled off to obtain a metal pattern.

[Example 2]
[Polymerization initiation layer forming step]
A polyimide film (product name: Kapton, manufactured by Toray DuPont) was used as a substrate, and the following polymerization initiation layer coating solution 2 was applied to the surface using a rod bar No. 18 and dried and crosslinked at 110 ° C. for 10 minutes. . The film thickness of the obtained polymerization initiation layer was 8.7 μm. Further, the same operation was performed on the back surface.

<Polymerization initiation layer coating solution 2>
・ 0.4 g of the specific polymerization initiating polymer B
・ TDI (Tolylene-2,4-diisocyanate) 0.16g
・ Methyl ethyl ketone (MEK) 1.6g

[Graft polymer formation process]
The coating liquid which consists of the following composition was apply | coated to the polyimide film in which the polymerization start layer was formed using rod bar # 18. The film thickness of the obtained film was 0.8 μm. Further, the same operation was performed on the back surface.

<Composition formation of coating solution>
・ Polymerizable group-containing polymer (synthesis method is shown below) 0.25 g
・ Cyclohexanone 8.0g

<Method for synthesizing the polymerizable group-containing polymer>
(Synthesis of monomer A)
In a 500 ml three-necked flask, 58.6 g of 2-hydroxyethyl methacrylate was added, 250 ml of acetone was added and stirred. After adding 39.2 g of pyridine and 0.1 g of p-methoxyphenol, the mixture was cooled in an ice bath containing ice water. After the temperature of the mixture became 5 ° C. or lower, 114.9 g of 2-bromoisobutanoic acid bromide was added dropwise using a dropping funnel over 3 hours. After completion of dropping, the ice bath was removed and the mixture was further stirred for 3 hours. The reaction mixture was poured into 750 ml of water and stirred for 1 hour. The aqueous mixture was extracted three times with 500 ml of ethyl acetate using a separatory funnel. The organic layer was washed successively with 500 ml of 1M hydrochloric acid, 500 ml of saturated aqueous sodium hydrogen carbonate solution and 500 ml of saturated brine. 100 g of magnesium sulfate was added to the organic layer, dehydrated and dried, and then filtered. The solvent was distilled off under reduced pressure to obtain 120.3 g of monomer A.

Next, 40 g of N, N-dimethylacetamide was placed in a 1000 ml three-necked flask and heated to 70 ° C. under a nitrogen stream. A solution of monomer A 12.58 g, methacrylic acid 27.52 g, V-601 (manufactured by Wako Pure Chemical Industries) 0.921 g in N, N-dimethylacetamide 40 g was added dropwise over 2.5 hours. After completion of dropping, the mixture was heated to 90 ° C. and further stirred for 2 hours. The reaction solution was cooled to room temperature and then poured into 3.5 L of water to precipitate a polymer compound. The precipitated polymer compound was collected by filtration, washed with water and dried to obtain 30.5 g of a polymer compound. As a result of measuring the mass average molecular weight of the obtained polymer compound by gel permeation chromatography (GPC) using polystyrene as a standard substance, it was 124,000.
In a 200 ml three-necked flask, 26.0 g of the polymer compound obtained and 0.1 g of p-methoxyphenol were added, dissolved in 60 g of N, N-dimethylacetamide and 60 g of acetone, and cooled in an ice bath containing ice water. After the temperature of the mixture became 5 ° C. or lower, 60.4 g of 1,8-diazabicyclo [5.4.0] -7-undecene (DBU) was added dropwise over 1 hour using a dropping funnel. After completion of dropping, the ice bath was removed and the mixture was further stirred for 8 hours. The reaction solution was poured into 2 L of water in which 17 ml of concentrated hydrochloric acid was dissolved to precipitate a polymerizable group-containing polymer. The precipitated polymerizable group-containing polymer was collected by filtration, washed with water, and dried to obtain 15.6 g.

  Next, exposure was performed for 5 minutes using a 1.5 kW high-pressure mercury lamp on both sides of the substrate. The film | membrane obtained after that was wash | cleaned with the saturated sodium hydrogen carbonate solution, and the board | substrate 2 by which the said polymeric group containing polymer was grafted on both surfaces was obtained.

[Metal film forming process]
The graft substrate 2 was immersed in an aqueous solution of 10% by mass of silver nitrate (manufactured by Wako Pure Chemical Industries) for 1 hour, and then washed with distilled water. Thereafter, electroless plating was performed for 10 minutes in the electroless plating bath used in Example 1. Further, electroplating was performed for 15 minutes in the electroplating bath used in Example 1 to produce a metal film 2 plated on both sides with copper.

[Etching process]
Photosensitive dry film (manufactured by Fuji Photo Film) is laminated on both sides of the obtained metal film 2, and a mask film on which a desired conductor circuit pattern is drawn (the metal pattern portion is an opening, and the metal pattern non-formed portion is a mask) Part) is exposed to ultraviolet light, the image is baked and developed, copper is removed from the non-metal part using a cupric chloride etchant, the dry film is peeled off, and a metal pattern in which both sides of the substrate are patterned is formed. Obtained.

(Through hole formation)
A through-hole formation (drilling) was performed on the obtained metal pattern using a carbon dioxide laser processing machine with a laser pulse energy of 60 mJ.
Next, a conductive paste was poured into the through hole, and the through hole was formed to connect the conductive patterns on the front and back surfaces.

[Example 3]
[Metal film forming process]
The graft substrate 1 produced in Example 1 was immersed in an aqueous solution of 0.1% by mass palladium nitrate (manufactured by Wako Pure Chemical Industries, Ltd.) for 30 minutes, and then washed with distilled water. Thereafter, electroless plating was performed for 10 minutes in the electroless plating bath used in Example 1. Furthermore, electroplating was performed for 3 minutes in the electroplating bath used in Example 1, and the metal film 3 was produced.
[Dry film pattern formation process]
A photosensitive dry film (manufactured by Fuji Photo Film) is laminated on the obtained metal film 3 and passed through a mask film on which a desired conductor circuit pattern is drawn (a metal pattern portion is an opening portion and a metal pattern non-forming portion is a mask portion). The image was printed by exposure to ultraviolet light and developed.
[Plating process, etching process]
The substrate on which the dry film was patterned was electroplated in the electroplating bath used in Example 1 for 15 minutes. Thereafter, the dry film was peeled off and the copper of the metal pattern non-metal part was removed using a cupric chloride etching solution, and then a metal pattern was obtained.

<Evaluation>
1. Measurement of Fine Line Width of Metal Pattern The fine line width of the metal patterns obtained in Examples 1 to 3 was measured using an optical microscope (trade name: OPTI PHOTO-2, manufactured by Nikon Corporation). The measurement results are shown in Table 1 below.
2. Etching removability The non-metallic pattern part was observed with a scanning electron microscope (SEM), and the presence or absence of the metal film was evaluated according to the following criteria. The results are shown in Table 1 below.
○: No metal film residue ×: Metal film residue

3. Adhesion Test An aluminum plate (0.1 mm) was adhered to the surface of the metal pattern obtained in Examples 1 to 3 with an epoxy adhesive (Araldite, manufactured by Ciba Geigy), dried at 140 ° C. for 4 hours, and then JISC6481. Based on this, a 90-degree peeling experiment was conducted. The results are shown in Table 1 below.

  As is apparent from Table 1, according to the present invention, a metal pattern having a width of 50 μm and 25 μm and excellent adhesion to the substrate could be formed. Further, it was found that there is no undesired residual metal film in the space, and the metal pattern non-formed portion is excellent in removability by etching.

Claims (7)

(A) A graft in which a polymerization initiating layer is formed by immobilizing a polymer having a functional group having a polymerization initiating ability on a side chain and a polymer having a crosslinkable group by a cross-linking reaction on a substrate, and directly bonded to the surface of the polymerization initiating layer Forming a polymer;
(B) forming a metal film on the graft polymer;
(C) etching the metal film;
A metal pattern forming method comprising: The step (a) includes a step of forming a polymerization initiating layer formed by immobilizing a polymer having a functional group having a polymerization initiating ability and a crosslinkable group on a side chain by a cross-linking reaction on the base (a- 1 ). a step of forming a graft polymer having (a-2) directly with the polymerization initiation layer surface throughout the polymerization initiation layer surface on the substrate bound and electroless plating catalyst or a precursor thereof that interact with the functional groups Have
The step (b) includes (b-1) a step of applying an electroless plating catalyst or a precursor thereof to the graft polymer, and (b-2) a step of performing electroless plating. The metal pattern forming method according to claim 1.   3. The method of forming a metal pattern according to claim 2, further comprising an electroplating step (b-3) after the step (b-2). The crosslinkable group is a crosslinkable group selected from a carboxylic acid group (—COOH), a hydroxyl group (—OH), an amino group (—NH ₂ ), and an isocyanate group (—NCO). The metal pattern formation method of any one of Claims 1-3.   On the base material, the formation of a polymerization initiating layer formed by immobilizing a polymer having a functional group having a polymerization initiating ability on a side chain and a polymer having a crosslinkable group by a cross-linking reaction results in a functional group having a side chain having a polymerization initiating ability and A polymerization initiation layer is formed using a polymer having a functional group and a crosslinking agent, wherein the crosslinking group is a hydroxyl group (-OH) and the crosslinking agent is a polyvalent isocyanate. The metal pattern formation method of any one of Claim 1 to 4. (A ′) On the substrate, a polymerization initiating layer is formed by immobilizing a functional group having a polymerization initiating ability in the side chain and a polymer having a crosslinkable group by a cross-linking reaction, and the surface of the polymerization initiating layer is polymerized. Forming a graft polymer by directly bonding a polymer having a functional group that interacts with a group and an electroless plating catalyst or a precursor thereof;
(B ′) a step of applying an electroless plating catalyst or a precursor thereof to the graft polymer, and then performing electroless plating to form a metal film;
(C) etching the metal film;
A metal pattern forming method comprising:   A monomer having a polymerizable group and a functional group that interacts with an electroless plating catalyst or a precursor thereof, a monomer having a functional group that interacts with the electroless plating catalyst or a precursor thereof, and a monomer having a double bond precursor Then, a polymer having a double bond introduced, or a polymer having a functional group that interacts with the electroless plating catalyst or its precursor and a monomer having a polymerizable group are reacted. The metal pattern forming method according to claim 6, wherein the polymer is a polymer obtained by introducing a double bond.