KR102322950B1 - Copper colloidal catalyst solution for electroless copper plating, electroless copper plating method, and manufacturing method of copper plating substrate - Google Patents

Abstract

A soluble copper salt (A) after adsorption promotion treatment (pretreatment) is performed by bringing a non-conductive substrate into contact with a liquid containing a surfactant; reducing agent (B); colloidal stabilizer (C); A catalyst is applied to a non-conductive substrate with a copper colloidal catalyst solution for electroless copper plating containing non-reducing oligosaccharides (D) such as sucrose and trehalose, and electroless copper plating is performed. Both time stability and continuity of catalytic activity are remarkably improved, and after increasing catalytic activity by adsorption promotion treatment (pre-treatment), a catalyst is applied and electroless copper plating is performed, so the appearance of the deposited copper film is excellent. .

Description

Copper colloidal catalyst solution for electroless copper plating, electroless copper plating method, and manufacturing method of copper plating substrate

The present invention relates to a copper colloidal catalyst solution for imparting a catalyst as a pretreatment when electroless copper plating is performed on a non-conductive substrate, an electroless copper plating method using the catalyst solution, and a copper film formed by the method It relates to a method for manufacturing a copper-plated substrate. The present invention relates to a copper colloidal catalyst liquid capable of providing excellent appearance to a copper film by remarkably improving time stability and continuity of catalytic activity.

Electroless copper plating on non-conductive substrates such as glass substrates and ceramic substrates as well as resin substrates such as glass/epoxy resin, glass/polyimide resin, epoxy resin, polyimide resin, polycarbonate resin, ABS resin, and PET resin In this case, it is common to first adsorb noble metals such as palladium, silver, platinum, etc. on a substrate, use it as a catalyst nucleus, and then deposit a copper film on the substrate with an electroless copper plating solution through the catalyst nucleus.

On the other hand, there is also a method of applying a catalyst using a specific metal such as copper, nickel, and cobalt, which is inexpensive without using a catalyst of a noble metal. In the catalyst solution of the specific metal, a soluble metal salt is treated with a reducing agent to generate colloidal particles of the metal. , making this the catalyst nucleus is the basic principle.

Among them, the prior art of a copper colloidal catalyst liquid is given, for example as follows.

(1) Patent Document 1

soluble copper salts; dispersants (gelatin, nonionic surfactants); A complexing agent (dicarboxylic acid, oxycarboxylic acid, etc.) is added, a reducing agent (sodium borohydride, dimethylamine borane, etc.) is added, and a stabilizer (sodium hypophosphite, dimethylamine borane, etc.) is added and electroless The preparation of a fine copper catalyst solution for copper plating is described.

(2) Patent Document 2

It is disclosed that a catalyst for electroless plating consisting of a copper salt (a copper amine complex in Production Example 2), a cationic surfactant, and a reducing agent is applied to a material to be plated, followed by electroless copper plating, followed by electroless copper plating (Claim 1-2, paragraph 42).

(3) Patent Document 3

Direct plating of copper onto a substrate is disclosed by applying a catalyst to a substrate with a copper(I) oxide colloidal catalyst solution, then immersing the substrate in a solution containing a copper salt, a reducing agent, and a complexing agent.

(4) Patent Document 4

The material to be plated is pretreated with a conditioning agent containing a surfactant (cationic, amphoteric, nonionic, etc.; paragraph 56), and cuprous salt, hypophosphite and chlorine ions, or additionally reducing agents (amine boranes, hydrogenation A method (claims 8 to 9, paragraph 70) of electroless copper plating by catalytic treatment with a catalyst solution containing boron, etc.) is disclosed.

Among the conditioning agents, it is described that, in particular, when a cationic surfactant is used, the hydrophilic group of the surfactant adsorbed to the material to be plated is negatively charged and the cuprous ion is easily adsorbed (paragraph 58).

(5) Patent Document 5

Treatment of a non-conductive substrate with a dispersion of an activator comprising a noble metal/metal-colloid (e.g., a colloidal solution of palladium/tin) followed by contact with a copper salt solution and a conductor solution comprising a complexing agent and a reducing agent Then, methods for electroless plating and electroplating are disclosed (paragraphs 1, 13, 24, 29, 65, Table 1).

In the catalyst solution, the basic principle is to treat a soluble metal salt with a reducing agent to produce metal fine particles, but the catalyst solution of this principle includes the catalyst solution of Patent Documents 1 to 5, and is generally time-stable. In particular, there is a problem in that it is not easy to ensure the continuity of the catalyst application operation and the electroless plating operation smoothly over a long period of time.

If the time stability is lowered, even if the catalyst is applied and electroless copper plating is applied, the coating does not precipitate well, or there is a plating defect in which the film does not deposit partially, or the plating film varies and the uniformity is deteriorated, etc. There is a problem of

For example, in the case of a copper film that is electroless-plated after being treated with a catalyst solution in the initial stage of preparing a plating bath, the lower the time stability when preparing the plating bath, the lower the appearance of the film, but the Time stability also needs to be considered. That is, even if the appearance of the coating film treated with the catalyst solution at the initial stage of preparing the plating bath is good, if the coating solution is treated with the catalyst solution several months after the plating bath preparation, there are few cases in which the plating defects or deviations occur in the appearance of the coating film. Therefore, the time stability of the catalyst solution is important.

Accordingly, the present inventors, as shown in Japanese Patent Application Laid-Open No. 2015-147987 (hereinafter referred to as Prior Invention 1), contain colloidal stabilizers such as oxycarboxylic acids and aminocarboxylic acids that stabilize copper salts in a copper catalyst solution. At the same time, by adjusting the mixing ratio of the copper salt and the stabilizer, and suppressing the content of the surfactant to a very small amount to zero, a copper colloidal catalyst solution in which the time stability of the catalyst solution is improved was proposed.

However, in consideration of improvement of the appearance of the copper film obtained by electroless plating and reduction of processing cost, it is required to further improve the time stability of the catalyst solution.

To this end, while paying attention to whether or not adding sugars to the catalyst solution has an effect on the time stability of the catalyst solution, examples of the prior art including the technical details of using sugars when applying the catalyst include the following same as

(6) Patent Document 6

It is a method of reducing a metal salt to a non-conductive substrate, subjecting it to a catalyst application treatment, and performing an electroless copper plating treatment (Claim 1, Paragraph 1). ), fructose (fructose), and reducing sugars such as wood sugar (xylose) (Claim 1, 10, Paragraphs 1, 24). It is also possible that the composition contains buffering agents such as citric acid, tartaric acid, malic acid and the like (paragraph 19).

As a similar prior document, there is Japanese Patent Application Laid-Open No. 2012-127002 (Rom & Haas).

(7) Patent Document 7

This is a method in which a metal salt (copper salt, etc.) is reduced on a non-conductive substrate, subjected to a catalyst provision treatment, and electroless copper plating treatment is performed (Claim 1, 3, Paragraph 29, Table 1). Examples of the reducing agent include glucose ( paragraph 25). In addition, by dissolving carboxylic acids such as tartaric acid, citric acid, and succinic acid, and sugars such as sucrose and fructose in the catalyst solution, the amount of catalyst metal adhered to the surface of the substrate increases (paragraph 31).

(8) Patent Document 8

It is a method of carrying out electroless copper plating after carrying out a catalyst provision process with not a copper catalyst liquid but a silver colloidal catalyst liquid (pretreatment liquid) (claims 1, 35).

In addition to oxycarboxylic acids such as citric acid, tartaric acid, lactic acid and malic acid (claims 1 and 3), known colloidal dispersants such as cellulose and derivatives thereof, monosaccharides, polysaccharides and derivatives thereof can be added to the catalyst solution (paragraph 46).

Monosaccharides, polysaccharides and their derivatives are sucrose, mannitol, sorbitol, glycerol, dextrin, and the like (paragraph 50).

(9) Patent Document 9

A non-conductive substrate made of a resin molded body is etched, brought into contact with a colloidal solution containing a noble metal compound (gold, silver, etc.) and stannous salt, and then brought into contact with an aqueous solution of a palladium compound to perform a catalyst application treatment, It is a method of performing copper plating treatment (claims 1 and 2).

It is possible to contain reducing saccharides such as glucose, sorbitol, cellulose, sucrose, mannitol, and gluconolactone in the electroless copper plating solution instead of the catalyst solution (paragraph 73).

(10) Patent Document 10

Etching is performed on non-conductive substrates such as resin, ceramics, and glass, sensitization treatment is performed by attaching tin salt (stannous chloride, etc.), immersed in silver nitrate solution, silver is substituted on tin, and tin-silver composite It is a method of growing, immersing in a reducing solution, activating, and then performing electroless copper plating (Claim 1 to 6, paragraphs 10 and 22), and it is possible to use glucose as the reducing solution.

Japanese Patent Application Laid-Open No. Hei 02-093076 Japanese Patent Application Laid-Open No. 10-229280 Japanese Patent Application Laid-Open No. Hei 07-197266 Japanese Patent Application Laid-Open No. 2011-225929 Japanese Patent Application Publication No. 2013-522476 Japanese Patent Application Laid-Open No. 2012-130910 Japanese Patent Application Laid-Open No. 2003-313670 Japanese Patent Application Laid-Open No. 2004-190042 Japanese Patent Application Laid-Open No. 2006-299366 Japanese Patent Application Laid-Open No. 2005-146330

In Patent Documents 6 to 10, saccharides such as glucose, fructose, maltose, and cellulose, or sugar alcohols such as mannitol and sorbitol are used in the catalyst solution serving as a pretreatment agent.

However, in Patent Document 9, sugars and sugar alcohols are used not for the catalyst solution but for the electroless copper plating solution.

The present invention makes it a technical subject to further improve the temporal stability of the copper colloidal catalyst solution by developing the characteristic component composition based on the prior invention 1 above.

The present inventors intensively studied the relationship between the copper colloidal catalyst liquid to which the saccharide which consists of saccharides and sugar alcohol was added, and its temporal stability, taking the said patent documents 6-10 as a starting point. As a result, the present inventors have found that when specific carbohydrates such as glucose, maltose, sorbitol, and xylitol are selected and added to the copper colloidal catalyst solution, the time stability of the catalyst solution is further improved than when no carbohydrates are included, and electroless plating It was found that a copper film having a good appearance can be formed by the , and a proposal as shown in Japanese Patent Application Laid-Open No. 2016-151056 (hereinafter referred to as Prior Invention 2) was made.

Here, the present inventors intensively studied the relationship between saccharides included in saccharides in a broad sense but outside the range specified in Prior Invention 2, and the temporal stability of the copper colloidal catalyst solution, in order to further materialize the above ideas. As a result, the present inventors have found that when a non-reducing oligosaccharide is used as a saccharide deviating from this regulation, the time stability of the copper colloidal catalyst solution and the continuity of catalytic activity are improved in the case of using the saccharide stipulated in Prior Invention 2 above. It was found that more improved efficacy can be expected when compared with , and completed the present invention.

That is, the present invention 1 is a copper colloidal catalyst solution for imparting a catalyst by contacting a non-conductive substrate to be subjected to electroless copper plating,

(A) soluble copper salts;

(B) a reducing agent;

(C) at least one colloidal stabilizer selected from the group consisting of oxycarboxylic acids, aminocarboxylic acids, and polycarboxylic acids;

(D) non-reducing oligosaccharides;

It is a copper colloidal catalyst solution for electroless copper plating, characterized in that it consists of.

This invention 2 is the copper colloidal catalyst liquid for electroless copper plating characterized by the above-mentioned this invention 1 further containing a reducing saccharide.

Invention 3 is for electroless copper plating according to the present invention 1 or 2, wherein the non-reducing oligosaccharide (D) is at least one selected from sucrose, trehalose, raffinose, and cyclodextrin. of copper colloidal catalyst.

In the present invention 4, in any one of the present inventions 1 to 3, the reducing agent (B) is a borohydride compound, amine boranes, hypophosphorous acids, aldehydes, ascorbic acids, hydrazines, polyhydric phenols, polyvalent naphthol It is a copper colloidal catalyst solution for electroless copper plating, characterized in that it is at least one selected from the group consisting of phenols, phenolsulfonic acids, naphtholsulfonic acids, and sulfonic acids.

In the present invention 5, in any one of the present inventions 1 to 4, in the colloidal stabilizer (C),

The oxycarboxylic acids are citric acid, tartaric acid, malic acid, gluconic acid, glucoheptonic acid, glycolic acid, lactic acid, trioxybutyric acid, ascorbic acid, isocitric acid, tartronic acid, glyceric acid, hydroxybutyric acid, leucine, citramalic acid , and at least one selected from the group consisting of salts thereof,

The aminocarboxylic acids are ethylenediaminetetraacetic acid, hydroxyethylethylenediaminetriacetic acid, diethylenetriaminepentaacetic acid, triethylenetetraminehexaacetic acid, ethylenediaminetetrapropionic acid, nitrilotriacetic acid, iminodiacetic acid, hydroxyethyl Iminodiacetic acid, iminodipropionic acid, 1,3-propanediaminetetraacetic acid, 1,3-diamino-2-hydroxypropanetetraacetic acid, glycol etherdiaminetetraacetic acid, metaphenylenediaminetetraacetic acid, 1,2-dia Minocyclohexane-N,N,N',N'-tetraacetic acid, diaminopropionic acid, glutamic acid, dicarboxymethylglutamic acid, ornithine, cysteine, N,N-bis(2-hydroxyethyl)glycine, (S, S)-ethylenediaminesuccinic acid, and at least one selected from the group consisting of salts thereof,

The polycarboxylic acids are at least one selected from the group consisting of succinic acid, glutaric acid, malonic acid, adipic acid, oxalic acid, maleic acid, citraconic acid, itaconic acid, mesaconic acid, and salts thereof. It is a copper colloidal catalyst liquid for electroless copper plating.

In the present invention 6,

(a) an adsorption promoting step (pre-treatment) in which a non-conductive substrate is brought into contact with a liquid containing at least one adsorption accelerator selected from the group consisting of a nonionic surfactant, a cationic surfactant, an anionic surfactant, and an amphoteric surfactant process);

(b) the non-conductive substrate subjected to the adsorption promoting treatment is brought into contact with the copper colloidal catalyst solution for electroless copper plating according to any one of the inventions 1 to 5, and the colloidal copper particles are adsorbed on the surface of the non-conductive substrate catalyst application process;

(c) an electroless plating step of forming a copper film using an electroless copper plating solution on the non-conductive substrate subjected to the catalyst application treatment;

It is an electroless copper plating method, characterized in that consisting of.

The present invention 7 is an electroless copper plating method according to the present invention 6, wherein the adsorption accelerator used in the adsorption promoting step (a) contains at least a cationic surfactant.

The present invention 8 is a method for manufacturing a copper-plated substrate, characterized in that a copper film is formed on a non-conductive substrate by the electroless copper plating method of the present invention 6 or 7.

In the present invention, since non-reducing oligosaccharides such as sucrose and trehalose are selectively used in place of the specific saccharides defined in Prior Invention 2, the time stability of the catalyst solution is significantly higher than in Prior Invention 2 , and the color tone and density of the copper film obtained by electroless plating are also improved.

In particular, in the present invention, the time stability of the colloidal catalyst solution after preparing the plating bath can be improved, and as will be described later, even if the catalyst is applied using the catalyst solution at the time of 3 months after the plating bath is prepared, A copper film having the same properties and state as in the case of using the catalyst solution immediately after preparing the plating bath can be formed, and the catalytic activity is excellent in durability. Therefore, according to the present invention, compared with the prior inventions 1 and 2, the maintenance of the catalyst solution can be further reduced, and the productivity of the electroless copper plating can be further improved.

In addition, if adsorption promotion treatment is performed with a surfactant before the catalyst is applied to the non-conductive substrate, the effect of the copper colloidal catalyst solution can be improved. In particular, when treated with a cationic surfactant, the effect of the copper colloidal catalyst solution is remarkably improved.

In Patent Document 8, it is disclosed that sucrose (sucrose) is contained in the catalyst solution in order to stabilize the colloid of the catalyst solution ([0046]), but it is not a copper catalyst solution but a silver catalyst solution; Moreover, in Example 19 which is the specific example of the only silver catalyst liquid containing a saccharide, sucrose is contained, but oxycarboxylic acids, aminocarboxylic acids, etc. are not contained, and it differs from this invention at the point.

In addition, although not included in the above-mentioned patent documents, as prior documents describing saccharides classified as non-reducing oligosaccharides used in the present invention, there are Japanese Patent Application Laid-Open No. 2014-180666 and Japanese Patent Application Laid-Open No. 2016-539244.

Among them, Japanese Patent Application Laid-Open No. 2014-180666 discloses a metal catalyst solution for electroless copper plating (claims 1 and 7), and the catalyst solution is a noble metal such as gold, silver, palladium ([0024] ); reducing agent ([0023]); Contains flavonoid glycosides to which sugars (trehalose, glucose, mannose, etc.) are bound ([0021]). However, since the metal contained in the catalyst solution is a noble metal and not copper, and also saccharides such as trehalose are formulated as a specific organic compound contained in the flavonoid skeleton, and are not directly incorporated as independent saccharide components, different from the present invention.

Similarly, Japanese Patent Laid-Open No. 2016-539244 discloses an electroless copper plating solution containing a copper salt, a reducing agent, and a complexing agent for forming a copper seed layer on the barrier layer (Claim 1), and water as the reducing agent A cross is illustrated (claim 5, [0040]). However, it is fundamentally different from the present invention in that the liquid containing the reducing agent is a plating liquid and not a catalyst liquid, and in that non-reducing sucrose is mistakenly classified as a reducing agent.

1st invention of this invention is made to contact a nonelectroconductive board|substrate, and to the copper colloidal catalyst liquid for providing a catalyst, (A) soluble copper salt; (B) a reducing agent; (C) colloidal stabilizers; Furthermore (D) it is a copper colloidal catalyst liquid for electroless copper plating containing a non-reducing oligosaccharide (the said invention 1).

In the second invention of the present invention, the non-conductive substrate is adsorption-promoted (pre-treatment) of the non-conductive substrate in advance with a liquid containing a surfactant (adsorption accelerator), and then a catalyst is applied using the copper colloidal catalyst liquid of the first invention, It is an electroless copper plating method in which a copper film is formed by performing copper plating (the present invention 6 above).

A third invention of the present invention is a method for manufacturing a copper-plated substrate in which a copper film is formed on a non-conductive substrate by the electroless copper plating method of the second invention (invention 8 above).

Examples of the non-conductive substrate include resin substrates such as glass/epoxy resin, glass/polyimide resin, epoxy resin, polyimide resin, polycarbonate resin, ABS resin, and PET resin, and other glass substrates, ceramic substrates, etc. have.

The essential components of the copper colloidal catalyst liquid of the present invention 1 are (A) a soluble copper salt; (B) a reducing agent; (C) colloidal stabilizers; (D) There are non-reducing oligosaccharides.

As the said soluble copper salt (A), if it is a soluble salt which generate|occur|produces a cuprous ion or cupric ion in aqueous solution, any thing can be used, There is no restriction|limiting in particular, A sparingly soluble salt is not excluded. Specifically, in addition to copper sulfate, copper oxide, copper chloride, copper pyrophosphate, and copper carbonate, copper carboxylate salts such as copper acetate, copper hydroxide and copper citrate, or organic sulfonic acids such as copper methanesulfonate and copper hydroxyethanesulfonate A copper salt etc. are mentioned, Copper sulfate, copper citrate, and copper methanesulfonate are preferable.

Examples of the reducing agent (B) include boron hydride compounds, amine boranes, hypophosphorous acids, aldehydes, ascorbic acids, hydrazines, polyhydric phenols, polyvalent naphthols, phenol sulfonic acids, naphthol sulfonic acids, sulfonic acids, and the like. have. The aldehydes include formaldehyde, glyoxylic acid, or a salt thereof. Polyhydric phenols include catechol, hydroquinone, resorcinol, pyrogallol, phloroglucin, and gallic acid. The phenolsulfonic acids include phenolsulfonic acid, cresolsulfonic acid, or a salt thereof.

The colloidal stabilizer (C) is a compound that forms a copper complex in the plating bath, and functions to ensure temporal stability of the catalyst solution.

The colloidal stabilizer (C) is selected from the group consisting of oxycarboxylic acids, aminocarboxylic acids, and polycarboxylic acids.

Examples of the oxycarboxylic acids include citric acid, tartaric acid, malic acid, gluconic acid, glucoheptonic acid, glycolic acid, lactic acid, trioxybutyric acid, ascorbic acid, isocitric acid, tartronic acid, glyceric acid, hydroxybutyric acid, leucine, citra. malic acid, and salts thereof.

Examples of the aminocarboxylic acids include ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid (HEDTA), diethylenetriaminepentaacetic acid (DTPA), triethylenetetraminehexaacetic acid (TTHA), ethylenediaminetetra Propionic acid, nitrilotriacetic acid (NTA), iminodiacetic acid (IDA), hydroxyethyliminodiacetic acid, iminodipropionic acid (IDP), 1,3-propanediaminetetraacetic acid, 1,3-diamino-2-hydroxy Propanetetraacetic acid, glycol etherdiaminetetraacetic acid, metaphenylenediaminetetraacetic acid, 1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid, diaminopropionic acid, glutamic acid, dicarboxymethylglutamic acid, ornithine, cysteine, N,N-bis(2-hydroxyethyl)glycine, (S,S)-ethylenediaminesuccinic acid, and salts thereof.

Examples of the polycarboxylic acids include succinic acid, glutaric acid, malonic acid, adipic acid, oxalic acid, maleic acid, citraconic acid, itaconic acid, mesaconic acid, and salts thereof.

The feature of the copper colloidal catalyst solution of the present invention 1 is that the non-reducing oligosaccharide (D) is selected and added. In the present invention, the oligosaccharide refers to a saccharide in which about 2 to 10 monosaccharides are condensed.

The non-reducing oligosaccharide (D) is selected from sucrose, trehalose, raffinose, cyclodextrin and the like, and these can be used alone or in combination, but sucrose and trehalose are preferable.

However, although cyclodextrin is a non-reducing oligosaccharide with a cyclic reducing end, the smaller the number of bonds is, the lower the solubility is when the number of bonds in the monosaccharide unit is large.

As will be described later, the pH of the colloidal copper catalyst liquid of the present invention has a value in an alkaline region or an acidic region except for neutrality, but the copper colloidal catalyst liquid of the present invention containing the non-reducing oligosaccharide (D) is acidic. Compared to the region, the alkaline region tends to easily enhance the catalytic function.

In Prior Invention 2, when specific carbohydrates such as glucose and maltose are blended into the catalyst solution, the time stability and the film appearance of the catalyst solution are effectively improved.

Therefore, also in the copper colloidal catalyst liquid of this invention characterized by containing the said non-reducing oligosaccharide (D), a reducing saccharide can be made to contain further.

Examples of the reducing saccharides include monosaccharides such as glucose (glucose), galactose, mannose, fructose (fructose) and wood sugar (xylose), and disaccharides such as maltose (maltose), isomaltose, lactose (lactose) and isomaltulose. , and trisaccharides such as maltotriose. In general, all monosaccharides belong to reducing saccharides because they have an aldehyde group.

Moreover, since specific sugar alcohol is also contained in the specific sugar prescribed|regulated in the said prior invention 2, also in the copper colloidal catalyst liquid of this invention, it is possible to contain the specific sugar alcohol prescribed|regulated in the prior invention 2. Sorbitol, xylitol, mannitol, maltitol, erythritol, lactitol etc. are mentioned as this sugar alcohol.

Since the copper colloidal catalyst liquid of this invention 1 is aqueous system, the solvent is water and/or hydrophilic alcohol, and the organic solvent (hydrophilic alcohol is included) is used independently normally.

Moreover, since the catalyst liquid tends to have low catalytic activity in the neutral vicinity of pH 6-8, it is preferable that the pH exists in the value of the acidic region or alkaline region excluding the said neutral region. Specifically, pH 1-6 and 8-12 are suitable, Preferably it is pH 2-5 and 8-11, When it adjusts to such an appropriate area|region, copper colloidal particle is easy to stabilize.

As described above, in the copper colloidal catalyst solution of the present invention containing the non-reducing oligosaccharide (D), the alkaline region tends to easily enhance the catalytic function as compared to the acidic region. For this reason, from the viewpoint of drawing out a catalytic function, for example, as a colloidal stabilizer (C), using aminocarboxylic acids, such as EDTA and NTA, is slightly compared to using oxycarboxylic acids, such as tartaric acid and citric acid. there is more dominance.

In the copper colloidal catalyst liquid, the soluble copper salt (A) may be used alone or in combination with others, and the mixing ratio thereof is preferably 0.005 mol/L to 3 mol/L, more preferably 0.05 mol. /L to 2 mol/L, more preferably 0.04 mol/L to 1.2 mol/L.

In the copper colloidal catalyst liquid, the reducing agent (B) may be used alone or in combination with others, and the mixing ratio thereof is preferably 0.005 mol/L to 4 mol/L, more preferably 0.01 mol/L to 3 mol/L, more preferably 0.02 mol/L to 2.2 mol/L. When the content of the reducing agent (B) is less than the appropriate amount, there is a problem that the reducing action of the soluble copper salt (A) is lowered. On the contrary, when the content of the reducing agent (B) is too large, the homogeneity of the copper film deposited by electroless plating may be lowered.

In the copper colloidal catalyst liquid, the colloidal stabilizer (C) may be used alone or in combination with others, and the mixing ratio thereof is preferably 0.005 mol/L to 4 mol/L, more preferably 0.01 mol/L L to 2 mol/L, more preferably 0.05 mol/L to 1.6 mol/L.

In the copper colloidal catalyst solution, the non-reducing oligosaccharide (D) may be used alone or in combination with others, and the mixing ratio thereof is preferably 0.001 mol/L to 4 mol/L, more preferably 0.01 mol. /L to 3 mol/L, more preferably 0.05 mol/L to 2.2 mol/L.

Moreover, as a reducing saccharide and sugar alcohol which the copper colloidal catalyst liquid of this invention can contain secondaryly, the specific example mentioned above is mentioned, These can be used independently or can be used with another thing. The content of the catalyst solution in total is preferably 0.001 mol/L to 2.0 mol/L, more preferably 0.01 mol/L to 1.5 mol/L, and still more preferably 0.05 mol/L to 1.0 mol/L. .

In the copper colloidal catalyst liquid, the content molar ratio of the soluble copper salt (A) and the colloidal stabilizer (C) is preferably (A): (C) = 1:0.03 to 1:35, more preferably (A): (C) = 1:0.5 to 1:24. When the relative content of the colloidal stabilizer (C) is too low, the time stability of the catalyst solution becomes low, which may eventually cause precipitation failure in the copper film obtained by electroless plating. Conversely, even if the relative content of the colloidal stabilizer (C) is too high, the time stability of the catalyst solution is lost, and there is a fear of reducing the quality of the copper film obtained.

In the copper colloidal catalyst liquid, the content molar ratio of the soluble copper salt (A) and the reducing agent (B) is preferably (A): (B) = 1: 0.01 to 1: 6, more preferably ( A): (B) = 1: 0.05 to 1: 4, even more preferably (A): (B) = 1: 0.1 to 1:2.

In the copper colloidal catalyst liquid, the content molar ratio of the soluble copper salt (A) and the non-reducing oligosaccharide (D) is preferably (A): (D) = 1: 0.01 to 1: 40, more preferably is (A): (D) = 1: 0.1 to 1: 25, even more preferably (A): (D) = 1: 0.1 to 1: 15. When the relative content of the non-reducing oligosaccharide (D) is too low, the time stability of the copper colloidal catalyst solution and the continuity of the catalytic activity may become low. Conversely, when the relative content of the non-reducing oligosaccharide (D) is too high, there is a fear that not only imparts catalyst nuclei to the non-conductive substrate, but also impairs formation of a film having a good appearance as a result.

In the preparation of the catalyst solution, in order to smoothly donate electrons from the reducing agent (B) to copper ions, a solution of the reducing agent (B) is added to a solution containing a soluble copper salt (A) (and a colloidal stabilizer (C)) for a period of time. It is basically performed by dropping liquid drops slowly and little by little. For example, a solution of the reducing agent (B) at preferably 5 ° C. to 50 ° C., more preferably 10 ° C. to 40 ° C. is slowly added dropwise to the solution of the soluble copper salt (A), preferably A catalyst liquid is prepared by stirring for 20 minutes - 1200 minutes, More preferably, it is 30 minutes - 300 minutes. However, it is also possible to drop the liquid drop of the solution of the soluble copper salt (A) into the solution of the reducing agent (B), conversely, when preparing the catalyst solution.

In the catalyst solution of the present invention, the copper colloidal particles generated from the soluble copper salt (A) by the action of the reducing agent (B) have a suitable average particle diameter of 1 nm to 250 nm, preferably 1 nm to 120 nm, more preferably 1 nm to It is a fine particle of 100 nm. When the average particle diameter of the copper colloidal particles is 250 nm or less, when the non-conductive substrate is brought into contact with the catalyst solution, the copper colloidal particles enter the concave portion of the fine concavo-convex surface of the substrate, are filled and densely adsorbed, or are not dropped by being caught. It can be estimated that provision of the copper colloidal nucleus in the substrate surface is promoted by the anchoring effect. Conversely, when the average particle diameter is larger than 250 nm, it is difficult to obtain a stable copper colloid due to aggregation, precipitation, separation, etc., and also because it is difficult to expect an anchoring effect, the copper colloidal particles are not provided only partially on the surface of the substrate, There is a possibility that the surface may become defective.

Although the copper colloidal catalyst liquid of this invention 1 can contain surfactant, since there exists a possibility that catalytic activity may become low, it is preferable to lower|hang the mixing ratio to a small amount of 950 mg/L or less.

The surfactant means a variety of nonionic surfactants, cationic surfactants, anionic surfactants, or amphoteric surfactants. In particular, amphoteric surfactants, cationic surfactants, anionic surfactants, or low molecular weight nonionic surfactants are not preferred.

Examples of the nonionic surfactant include C1-C20 alkanols, phenols, naphthols, bisphenols, (poly)C1-C25 alkylphenols, (poly)arylalkylphenols, C1-C25 alkylnaphthols, C1-C25 alkoxylated phosphoric acids ( salt), sorbitan ester, polyalkylene glycol, polyoxyalkylene alkyl ether, C1-C22 aliphatic amine, C1-C22 aliphatic amide, etc., by adding 2 to 300 moles of ethylene oxide (EO) and/or propylene oxide (PO) What was condensed, etc. are mentioned.

As said cationic surfactant, a quaternary ammonium salt, a pyridinium salt, etc. are mentioned. Specifically, ammonium salt of diarylamine polymer, lauryl trimethyl ammonium salt, stearyl trimethyl ammonium salt, lauryl dimethyl ethyl ammonium salt, octadecyl dimethyl ethyl ammonium salt, lauryl dimethyl benzyl ammonium salt, cetyl dimethyl benzyl ammonium salt, octadecyl dimethyl benzyl ammonium salt, Trimethylbenzylammonium salt, triethylbenzylammonium salt, dimethyldiphenylammonium salt, benzyldimethylphenylammonium salt, hexadecylpyridinium salt, laurylpyridinium salt, dodecylpyridinium salt, stearylamine acetate, laurylamine acetate, octadecylamine acetate and the like.

Examples of the anionic surfactant include alkyl sulfate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl phenyl ether sulfate, alkylbenzenesulfonate, {(mono, di, tri)alkyl} naphthalenesulfonate, and the like.

Carboxybetaine, imidazoline betaine, sulfobetaine, aminocarboxylic acid betaine etc. are mentioned as said amphoteric surfactant. Further, a sulfated adduct or a sulfonated adduct of a condensation product of ethylene oxide (EO) and/or propylene oxide (PO) with an alkylamine or diamine can also be used.

This invention 6 is the electroless copper plating method using the said copper colloidal catalyst liquid, and combines the following three processes in order.

(a) adsorption promotion process

(b) catalyst application process

(c) electroless plating process

The adsorption promotion step (a) is, in other words, a pretreatment step of the catalyst application step (b), and at least one selected from the group consisting of nonionic surfactants, cationic surfactants, anionic surfactants, and amphoteric surfactants. A step of bringing a non-conductive substrate into contact with a liquid containing an adsorption accelerator of will do

In the adsorption promoting step (a), since it is necessary to bring the non-conductive substrate into contact with the liquid containing the surfactant, it is basically immersing the substrate in the liquid containing the surfactant. It may be applied to the .

As in the present invention 7, from the viewpoint of promoting adsorption, a cationic surfactant or amphoteric surfactant having a positive charge is suitable, and in particular, it is more preferable to include at least a cationic surfactant. In addition, when a cationic surfactant and a small amount of a nonionic surfactant are used together, the adsorption promoting effect is further enhanced.

In the catalyst solution of the present invention, the copper colloidal particles produced by reacting the reducing agent (B) on the soluble copper salt (A) have a negative zeta potential. When treated by contacting with , the substrate tends to be positively charged, and the adsorption efficiency of colloidal copper particles onto the substrate in the next step is increased.

Specific examples of the surfactant are the same as the example of the surfactant described as an object to be suppressed in the catalyst solution of the present invention 1 above.

The content of the surfactant is preferably 0.05 g/L to 100 g/L, more preferably 0.5 g/L to 50 g/L. As for the temperature of the liquid containing surfactant, about 15 degreeC - about 70 degreeC is preferable, and, as for the time for a board|substrate to contact with the liquid containing surfactant, 0.5 minute - about 20 minutes are preferable.

The non-conductive substrate after the adsorption promotion step (a) is washed with purified water and then dried or not dried, and the process proceeds to the next catalyst application step (b).

In a catalyst provision process (b), a nonelectroconductive board|substrate is made to contact the said copper colloidal catalyst liquid, and copper colloidal particle is made to adsorb|suck on the surface of this nonelectroconductive board|substrate.

In the catalyst application step (b), since it is necessary to bring the non-conductive substrate into contact with the copper colloidal catalyst liquid, it is basic to immerse the substrate in the catalyst liquid, but the catalyst liquid is sprayed on the substrate or the catalyst liquid is applied to the substrate with a brush. You may apply, etc.

The temperature of the catalyst solution is preferably 5°C to 70°C, more preferably 15°C to 60°C. The time for contacting the substrate with the catalyst solution is preferably from 0.1 minutes to 20 minutes, more preferably from 0.2 minutes to 10 minutes. When making contact by immersion treatment, it is sufficient to immerse the substrate in a state in which it is stopped in the catalyst liquid, but stirring or flow may be performed.

Moreover, after the said catalyst application process (b), you may put the acid washing process further before the next electroless-plating process (c). If the pickling process is additionally added, it is possible to further enhance the activity of the catalytic activity compared to the case without the pickling process, and even for a substrate having a complex shape with pores or through-holes, plating thickness deviation or disconnection defect can be reliably prevented, and the adhesion of the copper film can be further improved.

In the acid washing treatment, the acid concentration is preferably 10 g/L to 200 g/L, more preferably 20 g/L to 100 g/L, and examples of the acid include inorganic acids such as sulfuric acid and hydrochloric acid, and organic sulfonic acids. , an organic acid such as carboxylic acid such as acetic acid, tartaric acid or citric acid can be used.

The acid washing treatment temperature is preferably 5°C to 70°C, more preferably 15°C to 60°C, and the treatment time is preferably 0.1 minutes to 20 minutes, more preferably 0.2 minutes to 10 minutes.

The non-conductive substrate brought into contact with the catalyst solution is washed with purified water and then dried or not dried, and the electroless plating step (c) proceeds.

In the electroless plating step (c), the electroless copper plating may be carried out in the same manner as in the prior art, and there is no restriction in particular. The temperature of the electroless copper plating solution is generally 15°C to 70°C, and preferably 20°C to 60°C.

It is also possible to employ|adopt air stirring, rapid liquid-flow stirring, mechanical stirring by a stirring blade, etc. for stirring of a copper plating solution.

The present invention 8 is a method for manufacturing a copper plated substrate in which a copper film is formed on a non-conductive substrate by the electroless copper plating method, the adsorption promoting step (a), the catalyst application step (b) of the present invention 6, and Through the electroless plating step (c), a copper film is formed on the non-conductive substrate.

As mentioned above, the non-conductive substrate is a resin substrate such as glass/epoxy resin, glass/polyimide resin, epoxy resin, polyimide resin, polycarbonate resin, ABS resin, PET resin, or glass substrate, ceramic substrate, etc. say

The composition of the electroless copper plating solution is not particularly limited, and a known copper plating solution can be used.

The electroless copper plating solution basically contains a soluble copper salt, a reducing agent, and a complexing agent, and may further contain various additives such as a surfactant and a pH adjuster, an acid, and the like.

About a soluble copper salt, it is the same as what was said with the said copper colloidal catalyst liquid.

The reducing agent contained in the electroless copper plating solution is the same as the above-mentioned copper colloidal catalyst solution, including formaldehyde (formalin water), hypophosphorous acids, phosphorous acids, amine boranes, boron hydrides, glyoxylic acid. etc. are mentioned, and formalin water is preferable.

About the complexing agent contained in the electroless copper plating liquid, it is common with the example of the colloidal stabilizer mentioned in the said copper colloidal catalyst liquid. Specifically, ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), triethylenetetraminehexaacetic acid (TTHA), hydroxyethylethylenediaminetriacetic acid (HEDTA), nitrilotriacetic acid (NTA), Aminocarboxylic acids such as iminodiacetic acid (IDA), polyamines such as ethylenediamine, tetramethylenediamine, hexamethylenediamine, diethylenetriamine, tetraethylenepentamine and pentaethylenehexamine, monoethanolamine, diethanolamine , amino alcohols such as triethanolamine, oxycarboxylic acids such as citric acid, tartaric acid, lactic acid, malic acid, thioglycolic acid, glycine, and the like.

The electroless copper plating solution may contain an organic acid, an inorganic acid, or a salt thereof as a liquid base component.

As said inorganic acid, sulfuric acid, pyrophosphoric acid, tetrafluoroboric acid, etc. are mentioned. Moreover, as an organic acid, organic sulfonic acids, such as oxycarboxylic acid, such as glycolic acid and tartaric acid, methanesulfonic acid, 2-hydroxyethanesulfonic acid, etc. are mentioned.

Example

Hereinafter, while explaining the Example of the electroless copper plating method containing the preparation of the adsorption accelerator containing liquid which concerns on this invention, a copper colloidal catalyst liquid, and an electroless copper plating liquid, the time stability of a copper colloidal catalyst liquid, a catalyst Examples of evaluation tests for the continuity of activity and the appearance of the copper film obtained in Examples below will be described in order.

In addition, the present invention is not limited to the following Examples and Test Examples, and of course, it can be arbitrarily changed within the scope of the technical spirit of the present invention.

«Example of electroless copper plating method»

Among the following Examples 1 to 14, the liquid containing the adsorption accelerator of Example 1 and the copper colloidal catalyst liquid contain the following components, respectively.

(Liquid containing adsorption accelerator)

Cationic surfactant: quaternary ammonium salt of diarylamine polymer

Nonionic surfactant: polyoxyalkylene branched chain decyl ether

(Copper Colloidal Catalyst Liquid)

Soluble copper salt (A): copper sulfate

Reducing agent (B): sodium borohydride

Colloidal stabilizer (C): tetrasodium ethylenediaminetetraacetate (EDTA·4Na)

Non-reducing oligosaccharide (D): sucrose

Examples 2-5, 7, 9, 11, and 13 are examples based on Example 1.

Example 2: Changing the non-reducing oligosaccharide (D) to trehalose

Example 3: Using together sucrose and trehalose as non-reducing oligosaccharides (D)

Example 4: Changing the non-reducing oligosaccharide (D) to raffinose

Example 5: Use of non-reducing oligosaccharide (D) (sucrose) and reducing saccharide (fructose) together

Example 7: Changing the colloidal stabilizer (C) to iminodiacetic acid

Example 9: Colloidal stabilizer (C) was changed to citrate

Example 11: Changing the reducing agent (B) to dimethylamine borane

Example 13: Adsorption promoter was changed to lauryldimethylbenzylammonium chloride and polyoxyalkylene branched decyl ether

Examples 6, 8, 10, 12, and 14 are examples based on the second embodiment.

Example 6: Use of a non-reducing oligosaccharide (D) (trehalose) and a reducing saccharide (maltose) together

Example 8: Colloidal stabilizer (C) was changed to nitrilotriacetate

Example 10: Colloidal stabilizer (C) was changed to citrate

Example 12: Changing the reducing agent (B) to dimethylamine borane

Example 14: Adsorption promoter was changed to lauryldimethylbenzylammonium chloride and polyoxyalkylene branched decyl ether

On the other hand, the following reference examples 1 to 3 are examples in which the copper colloidal catalyst solution contains the specific saccharide specified in the prior invention 2 based on the aforementioned prior invention 2. The specific carbohydrates are as follows.

Reference Example 1: Reducing disaccharide (maltose)

Reference Example 2: Reducing monosaccharide (glucose)

Standard Example 3: Sugar alcohol (xylitol)

In addition, the following comparative examples 1-3 are examples abbreviate|omitted as follows.

Comparative Example 1: Example in which the copper colloidal catalyst solution does not contain a non-reducing oligosaccharide (D)

Comparative Example 2: Example in which the copper colloidal catalyst solution contains saccharides (starch) other than the specific saccharides stipulated in Prior Invention 2, instead of the non-reducing oligosaccharide (D)

Comparative Example 3: An example in which the electroless plating process (c) was performed directly from the catalyst application process (b) without the adsorption promotion process (a)

(1) Example 1

≪Sequence of Adsorption Acceleration, Catalyst Application, and Electroless Plating≫

First, a glass/epoxy resin substrate not coated with copper foil (FR-4 manufactured by Panasonic Electric Co., Ltd., plate thickness: 1.0 mm) was used as a non-conductive sample substrate.

Then, the sample substrate is subjected to an adsorption accelerating treatment using the liquid containing the adsorption accelerator of (a) below, followed by immersion in the copper colloidal catalyst liquid as shown below (b) to perform a catalyst application treatment, and then Electroless plating was performed with a copper plating solution.

Specifically, the sample substrate was immersed in a liquid containing the following adsorption accelerator under conditions of 50°C for 2 minutes, and washed with purified water. Next, the sample board|substrate which performed the adsorption-accelerating process (pre-treatment) was immersed in the following copper colloidal catalyst liquid on 25 degreeC, conditions for 10 minutes, and it wash|cleaned with purified water. Thereafter, the sample substrate subjected to the catalyst application treatment was immersed in the following electroless copper plating solution, electroless plating was performed at 50° C. for 10 minutes to form a copper film on the sample substrate, washed with purified water and dried did.

(a) Preparation of adsorption accelerator-containing liquid

The liquid containing the adsorption accelerator was adjusted with the following composition.

[Liquid containing adsorption accelerator]

Quaternary ammonium salt of diarylamine polymer 6g/L

Polyoxyalkylene branched chain decyl ether 3 g/L

pH 11.0

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA 4Na 0.4 mol/L

Sucrose 0.5 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.0, and it stirred for 45 minutes, and prepared the copper colloidal catalyst liquid.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 15 nm.

(c) Preparation of electroless copper plating solution

An electroless copper plating solution was prepared with the following composition. The pH of the plating solution was adjusted with the following sodium hydroxide.

[Electroless copper plating solution]

Copper sulfate pentahydrate (as Cu ²⁺ ) 2.0 g/L

Formaldehyde 5.0 g/L

EDTA 30.0 g/L

Sodium hydroxide 9.6 g/L

purified water rest

pH (20°C) 12.8

(2) Example 2

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared as the following composition based on Example 1 above. The treatment conditions were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA 4Na 0.4 mol/L

Trehalose 0.5 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 25 nm.

(3) Example 3

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared as the following composition based on Example 1 above. The treatment conditions were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA 4Na 0.4 mol/L

Sucrose 0.2 mol/L

Trehalose 0.3 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.0, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 25 nm.

(4) Example 4

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared as the following composition based on Example 1 above. The treatment conditions were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA 4Na 0.4 mol/L

Raffinose 0.5 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 10.0, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated colloidal copper particle was about 30 nm.

(5) Example 5

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared as the following composition based on Example 1 above. The treatment conditions were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA 4Na 0.4 mol/L

Sucrose 0.4 mol/L

Fructose 0.1 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.0, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): (non-reducing oligosaccharide (D) + reducing saccharide) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 40 nm.

(6) Example 6

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared according to the following composition based on Example 2 above. The treatment conditions were the same as in Example 2.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA 4Na 0.4 mol/L

Trehalose 0.3 mol/L

Maltose 0.2 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): (non-reducing oligosaccharide (D) + reducing saccharide) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated colloidal copper particle was about 30 nm.

(7) Example 7

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared as the following composition based on Example 1 above. The treatment conditions were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

Iminodiacetic acid 0.4 mol/L

Sucrose 0.5 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 25 nm.

(8) Example 8

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared according to the following composition based on Example 2 above. The treatment conditions were the same as in Example 2.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

Trisodium nitrilotriacetate 0.4 mol/L

Trehalose 0.5 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 15 nm.

(9) Example 9

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared as the following composition based on Example 1 above. The treatment conditions were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

Trisodium citrate 0.3 mol/L

Sucrose 0.4 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 35 degreeC adjusted to pH 5.0, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:3

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:4

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 35 nm.

(10) Example 10

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared according to the following composition based on Example 2 above. The treatment conditions were the same as in Example 2.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

Trisodium citrate 0.3 mol/L

Trehalose 0.4 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 35 degreeC adjusted to pH 5.0, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:3

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:4

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 45 nm.

(11) Example 11

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared as the following composition based on Example 1 above. The treatment conditions were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA 4Na 0.4 mol/L

Sucrose 0.5 mol/L

[Reducing agent solution]

Dimethylamine borane 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 25 nm.

(12) Example 12

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared according to the following composition based on Example 2 above. The treatment conditions were the same as in Example 2.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA·4Na 0.4 mol/L

Trehalose 0.5 mol/L

[Reducing agent solution]

Dimethylamine borane 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 25 nm.

(13) Example 13

The composition of the electroless copper plating solution and the adsorption promotion, catalyst application, and each step of electroless plating, except that the liquid containing the adsorption accelerator and the colloidal copper catalyst liquid were respectively prepared in the following composition based on Example 1 above Treatment conditions were the same as in Example 1.

(a) Preparation of adsorption accelerator-containing liquid

The liquid containing the adsorption accelerator was adjusted with the following composition.

[Liquid containing adsorption accelerator]

Lauryldimethylbenzylammonium chloride 5g/L

Polyoxyalkylene branched chain decyl ether 1 g/L

pH 10.0

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA·4Na 0.4 mol/L

Sucrose 0.5 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 25 nm.

(14) Example 14

The composition of the electroless copper plating solution based on Example 2 above, and each of the adsorption accelerator containing liquid and the copper colloidal catalyst liquid were prepared to the following compositions, and each step of adsorption promotion, catalyst application, and electroless plating Treatment conditions were the same as in Example 2.

(a) Preparation of adsorption accelerator-containing liquid

The liquid containing the adsorption accelerator was adjusted with the following composition.

[Liquid containing adsorption accelerator]

Lauryldimethylbenzylammonium chloride 5g/L

Polyoxyalkylene branched chain decyl ether 1 g/L

pH 10.0

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA·4Na 0.4 mol/L

Trehalose 0.5 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): non-reducing oligosaccharide (D) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 25 nm.

(15) Standard Example 1

This is an example based on the above-mentioned prior invention 2, and the copper colloidal catalyst solution contains the reducing disaccharide (maltose), which is the specific saccharide specified in the prior invention 2, and does not contain the non-reducing oligosaccharide (D) used in the present invention.

That is, based on Example 1 above, except that the copper colloidal catalyst solution was prepared with the following composition, the composition of the adsorption accelerator containing liquid and the composition of the electroless copper plating solution, and the adsorption promotion, catalyst provision, and electroless plating were performed. The treatment conditions of each step were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA·4Na 0.4 mol/L

Maltose 0.5 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): saccharide (maltose) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 35 nm.

(16) Standard Example 2

This is an example based on the aforementioned Prior Invention 2, and the copper colloidal catalyst solution contains the reducing monosaccharide (glucose), which is the specific saccharide specified in Prior Invention 2, and does not contain the non-reducing oligosaccharide (D) used in the present invention.

That is, based on Example 1 above, except that the copper colloidal catalyst solution was prepared with the following composition, the composition of the adsorption accelerator containing liquid and the composition of the electroless copper plating solution, and the adsorption promotion, catalyst provision, and electroless plating were performed. The treatment conditions of each step were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA·4Na 0.4 mol/L

Glucose 0.5 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): Carbohydrate (glucose) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 35 nm.

(17) Standard example 3

This is an example based on the preceding invention 2, and the copper colloidal catalyst solution contains a sugar alcohol (xylitol), which is a specific saccharide specified in the prior invention 2, and does not contain the non-reducing oligosaccharide (D) used in the present invention.

That is, based on Example 1 above, except that the copper colloidal catalyst solution was prepared with the following composition, the composition of the adsorption accelerator containing liquid and the composition of the electroless copper plating solution, and the adsorption promotion, catalyst provision, and electroless plating were performed. The treatment conditions of each step were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA·4Na 0.2 mol/L

Xylitol 0.3 mol/L

[Reducing agent solution]

Dimethylamine borane 0.02 mol/L

Ascorbic acid 0.18 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:2

Soluble copper salt (A): saccharide (xylitol) = 1:3

Soluble copper salt (A): reducing agent (B) = 1:2

The average particle diameter of the produced|generated copper colloidal particle was about 45 nm.

(18) Comparative Example 1

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared as the following composition based on Example 1 above. The treatment conditions were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA·4Na 0.4 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 35 nm.

(19) Comparative Example 2

The composition of the liquid containing the adsorption accelerator and the composition of the electroless copper plating liquid, and each step of adsorption promotion, catalyst application, and electroless plating, except that the copper colloidal catalyst liquid was prepared as the following composition based on Example 1 above. The treatment conditions were the same as in Example 1.

(b) Preparation of copper colloidal catalyst solution

[Copper solution]

Copper sulfate (as Cu ²⁺ ) 0.1 mol/L

EDTA·4Na 0.4 mol/L

Starch 0.5 mol/L

[Reducing agent solution]

Sodium borohydride 0.02 mol/L

The reducing agent solution was dripped at the said copper solution of 25 degreeC adjusted to pH 9.5, and it stirred for 45 minutes, and the copper colloidal catalyst liquid was prepared.

The molar ratio of each component of the catalyst solution is as follows.

Soluble copper salt (A): colloidal stabilizer (C) = 1:4

Soluble copper salt (A): sugar (starch) = 1:5

Soluble copper salt (A): reducing agent (B) = 1:0.2

The average particle diameter of the produced|generated copper colloidal particle was about 500 nm.

(20) Comparative Example 3

It is an example which is based on the said Example 1 and abbreviate|omitted the adsorption promotion process.

That is, the sample substrate is directly immersed in the copper colloidal catalyst solution (b) of Example 1 to impart a catalyst without adsorption promoting treatment, and further electroless plating with the electroless copper plating solution (c) of Example 1 did The processing conditions of each process of catalyst provision and electroless plating, and each preparation conditions of a copper colloidal catalyst liquid and an electroless copper plating liquid are the same as that of Example 1.

For Examples 1 to 14, Standard Examples 1 to 3, and Comparative Examples 1 to 3, the type of adsorption accelerator (surfactant), the composition of the copper colloidal catalyst solution, and the average particle diameter of the copper colloidal particles are shown in Table 1 and Table 2 summarized.

<<Example of appearance evaluation test of a copper film deposited by electroless copper plating>>

For each copper colloidal catalyst solution prepared in the plating bath in Examples 1 to 14, Standard Examples 1 to 3, and Comparative Examples 1 to 3, when the catalyst solution in the initial stage of plating bath preparation was used, the appearance of the obtained copper film was visually observed. was observed and evaluated based on the following evaluation criteria.

(Evaluation standard)

(circle): The copper film was uniform and there was no dispersion|variation.

(triangle|delta): The dispersion|variation and non-precipitation of a part (plating defect) were confirmed in the copper film.

x: A copper film did not precipitate.

In addition, 'deviation' in the coating means that it is confirmed that there is a portion where the denseness or smoothness of the coating is different from that of the surrounding. The 'deviation' of the coating is different from the 'uniformity' of the coating.

«Example of time stability test of colloidal copper catalyst solution»

With respect to each copper colloidal catalyst solution for which the plating bath was prepared in Examples 1 to 14, Standard Examples 1 to 3, and Comparative Examples 1 to 3, the colloidal temporal stability was evaluated based on the following evaluation criteria.

In addition, in the evaluation criteria of the time stability, the evaluation of ◎ is, in the aforementioned invention 2, the point of '2 months after preparation of the plating bath' as the branch point of evaluation, but in the present invention, the 'plating bath longer than that of the prior invention 2' The time point of 3 months after preparation was taken as the bifurcation point of the evaluation.

(Evaluation standard)

(double-circle) : Even if 3 months or more passed after plating bath preparation, it did not precipitate or decompose|disassemble.

○: There was no precipitation or decomposition over 1 to 2 months after plating bath preparation.

△: Precipitation or decomposition within 1 month after plating bath preparation.

×: Colloidal particles were not generated, or precipitated or decomposed immediately after plating bath preparation.

«Example of catalytic activity persistence in copper colloidal catalyst solution»

For each copper colloidal catalyst solution prepared for plating baths in Examples 1 to 14, Standard Examples 1 to 3, and Comparative Examples 1 to 3, the continuity of catalytic activity was evaluated based on the following evaluation criteria.

In addition, the 'time stability of the catalyst solution' in the above test example is for the main purpose of observation of the shape of the catalyst solution itself, and the 'continuity of catalytic activity' of the test example is whether the catalyst imparting function is maintained or not, The main purpose was to observe the effectiveness of the function.

(Evaluation standard)

○: When the catalyst was applied with a catalyst solution 3 months after preparation of the plating bath, a uniform and non-uniform copper film was obtained.

(triangle|delta): When a catalyst was applied with the catalyst liquid 3 months after plating bath preparation, dispersion|variation or non-precipitation (plating defect) was confirmed in a part of copper film.

x: Although the catalyst was applied with the catalyst liquid which had passed 3 months after plating bath preparation, the copper film was not obtained.

≪Test results of the appearance of the copper film and the temporal stability of the copper colloidal catalyst solution and the continuity of the catalytic activity≫

Table 3 below shows these test results. In Table 3, 'appearance' refers to the appearance of the copper film, 'stability' refers to the temporal stability of the copper colloidal catalyst solution, and 'continuous active state' refers to the continuity of the catalytic activity of the copper colloidal catalyst solution.

However, the durability test of catalyst activity focuses on the activity of the catalyst solution itself, and it is meaningless to explain it in combination with the adsorption promotion process. Therefore, in Comparative Example 3 based on Example 1 and omitting the adsorption promotion process, the catalytic activity persistence test itself was omitted. In Table 3, '--' means omitted.

«Comprehensive evaluation of the temporal stability of the copper colloidal catalyst liquid and the continuity of catalytic activity, and the appearance of the copper film»

In Comparative Example 1 in which the copper colloidal catalyst solution does not contain the non-reducing oligosaccharide (D) used in the present invention, the time stability of the catalyst solution is Δ evaluation because 3 months after plating bath preparation is used as the evaluation standard, and the catalytic activity is Persistence was a × rating. In addition, about the external appearance of a copper film, since a catalyst liquid contains a reducing agent (B) and a colloidal stabilizer (C), it was evaluation (circle).

In Comparative Example 2, in which a colloidal stabilizer (B) and a saccharide coexist in a catalyst solution, but a starch different from the non-reducing oligosaccharide (D) used in the present invention as the saccharide, the time stability is lowered (x evaluation), and the resulting The average particle diameter of the copper particles is about 500 nm, that is, they are not colloidal particles. Therefore, plating defects were confirmed in the obtained copper film, and a problem arose in the film appearance (triangle|delta evaluation). In addition, since the time stability of a catalyst liquid was x evaluation, of course, the sustainability of catalyst activity was also x evaluation.

In Comparative Example 3, in which the catalyst was applied directly to the non-conductive substrate without adsorption promoting treatment and electroless copper plating was performed, the time stability of the catalyst solution was similar to that of the Example, but plating defects were confirmed in the deposited copper film. From this, it can be judged that the adsorption of the colloidal copper particles on the substrate is inferior compared with the examples due to the lack of the adsorption promoting treatment (pretreatment) before the catalyst is applied, and the lack of catalytic activity (the appearance of the copper film is × rating).

In Standard Examples 1 to 3, in which the specific carbohydrate specified in Prior Invention 2 was used instead of the non-reducing oligosaccharide (D) used in the present invention as the catalyst solution, 1 to 2 months have elapsed after the plating bath of the catalyst solution is prepared. Even if it did, the time stability in which precipitation did not generate|occur|produce was shown (circle evaluation), and the external appearance of the copper film was also favorable (circle evaluation). However, with respect to the catalyst liquid 3 months after preparation of the plating bath, the continuity of the catalyst activity was evaluated by Δ.

In Examples 1 to 14 in which adsorption promotion treatment (pretreatment) was performed, catalyst application treatment was performed, and then electroless copper plating was performed, the catalyst solution at the time of 3 months after plating bath preparation was all excellent in time stability and (double-circle evaluation), the copper film deposited by electroless plating showed an excellent external appearance with almost no dispersion|variation or plating defect (circle evaluation). In addition, even when the catalyst was applied using the catalyst solution 3 months after the plating bath preparation, a copper film with good appearance was obtained, and the catalytic activity was excellent in the same way as when the catalyst solution was used immediately after the plating bath preparation ( ○ evaluation).

When the Standard Examples 1 to 3 are compared with Comparative Example 1, in order to maintain the time stability of the catalyst solution well at the time point 1 to 2 months after the plating bath preparation, the specific carbohydrates specified in Prior Invention 2 are required. (change from △ evaluation to ○ evaluation). In addition, it can be seen that the durability of the catalyst activity is improved to some extent by the inclusion of this specific saccharide (changed from x evaluation to Δ evaluation).

Here, when Examples 1 to 14 are compared with those of Reference Examples 1 to 3, the specific carbohydrates specified in Prior Invention 2 are necessary to maintain the time stability of the catalyst solution well at the time when 3 months have elapsed after plating bath preparation. is not sufficient, it can be seen that the non-reducing oligosaccharide (D) prescribed in the present invention is required (changed from ○ evaluation to ◎ evaluation).

In addition, it can be seen that if the non-reducing oligosaccharide (D) specified in the present invention is contained in the catalyst solution instead of the specific saccharide specified in Prior Invention 2, the continuity of the catalytic activity is remarkably improved (○ evaluation in △ evaluation) changed to).

As described above, from the viewpoint of time stability and continuity of catalytic activity, the superiority of each catalyst solution of Examples 1 to 14 over each catalyst solution of Reference Examples 1 to 3 is clear, and non-reducing oligosaccharides defined in the present invention as saccharides When (D) is selected, the maintenance of the copper colloidal catalyst solution can be greatly simplified compared to the standard example, and there is an advantage that the plating process cost can be reduced.

Next, Examples 1 to 14 were studied in detail.

Example 1 was used as a reference, and relative evaluation with other examples was described. In Example 1, a non-conductive substrate was subjected to adsorption promotion treatment (pretreatment) with an adsorption accelerator containing a quaternary ammonium salt of diarylamine polymer as a cationic surfactant, copper sulfate was converted to a soluble copper salt (A), and hydrogenation was performed. After the catalyst was provided with a copper colloidal catalyst solution containing sodium boron as a reducing agent (B), ethylenediaminetetraacetate as a colloidal stabilizer (C), and sucrose as a non-reducing oligosaccharide (D), the catalyst was applied, and then electroless This is an example of copper plating. In Example 1, both the time stability of the catalyst solution and the continuity of catalyst activity were good, and when the catalyst solution was used immediately after plating bath preparation or 3 months after plating bath preparation, all copper films obtained by electroless plating were used. Silver, precipitation deviation or plating defects were not observed, and an excellent appearance was exhibited.

Example 2 is an example in which the non-reducing oligosaccharide (D) was changed to trehalose in Example 1. In Example 2, similarly to Example 1, the time stability of the catalyst solution and the continuity of catalyst activity were good, and the obtained copper film showed the outstanding external appearance.

Example 3 is an example in which sucrose and trehalose are used together as the non-reducing oligosaccharide (D), and Example 4 is an example in which raffinose is used as the non-reducing oligosaccharide (D). In Examples 3 to 4, as in Example 1, high temporal stability and continuity of catalytic activity, and excellent film appearance were exhibited.

Examples 5 to 6 are examples in which the non-reducing oligosaccharide (D) defined in the present invention and the reducing saccharide (fructose, maltose), which are specific saccharides specified in Prior Invention 2, are used together. As expected, Examples 5 to 6 exhibited high temporal stability and continuity of catalytic activity, and excellent film appearance, as in Examples 1 or 2. Based on this, it can be determined that even when the non-reducing oligosaccharide (D) and the reducing saccharide are used together, the synergistic effect of both does not appear in particular, while the reducing saccharide does not interfere with the effect of the non-reducing oligosaccharide (D). .

Examples 7-10 are examples in which the colloidal stabilizer (C) is changed in the catalyst liquid of Example 1 or 2, and Examples 11-12 are the reducing agent (B) in the catalyst liquid of Example 1 or 2 This is an example of a change. In Examples 7 to 12, high temporal stability and continuity of catalytic activity, and excellent film appearance were exhibited, as in Examples 1 or 2 serving as the basis thereof.

Examples 13 to 14 are examples in which the adsorption accelerator used in the adsorption promoting step (a) in Examples 1 or 2 was changed. As expected, Examples 13 to 14 exhibited high temporal stability and continuity of catalytic activity, and excellent film appearance, as in Examples 1 or 2 based on the results.

Examples 9 to 10 are examples in which a citrate is used as the colloidal stabilizer (C) and the pH of the catalyst solution is set to an acidic region. As the colloidal stabilizer (C), EDTA·4Na, iminodiacetic acid, etc. were used and the pH of the catalyst solution was set in the alkaline range. As in Examples 1 to 8 and 11 to 14, in Examples 9 to 10, the catalyst solution was There was no change in the evaluation of time stability and continuity of catalyst activity, and the appearance of the film.

The copper colloidal catalyst liquid of this invention improves time stability and continuity of catalytic activity remarkably, When electroless copper plating is carried out using this copper colloidal catalyst liquid, the outstanding external appearance will be provided to the copper film obtained.

Claims (8)

A copper colloidal catalyst solution for imparting a catalyst by contacting a non-conductive substrate to be subjected to electroless copper plating,
(A) soluble copper salts;
(B) a reducing agent;
(C) at least one colloidal stabilizer selected from the group consisting of oxycarboxylic acids, aminocarboxylic acids, and polycarboxylic acids;
(D) non-reducing oligosaccharides;
including,
Content of the said non-reducing oligosaccharide (D) in a copper colloidal catalyst liquid is 0.3 mol/L - 2.2 mol/L, The copper colloidal catalyst liquid for electroless copper plating characterized by the above-mentioned. According to claim 1,
Furthermore, it contains a reducing saccharide, The copper colloidal catalyst liquid for electroless copper plating characterized by the above-mentioned. 3. The method of claim 1 or 2,
The non-reducing oligosaccharide (D) is at least one selected from sucrose, trehalose, raffinose, and cyclodextrin, a copper colloidal catalyst solution for electroless copper plating. 3. The method of claim 1 or 2,
The reducing agent (B) is a boron hydride compound, amine boranes, hypophosphorous acids, aldehydes, ascorbic acids, hydrazines, polyhydric phenols, polyvalent naphthols, phenol sulfonic acids, naphthol sulfonic acids, and sulfonic acids. Copper colloidal catalyst solution for electroless copper plating, characterized in that it is at least one selected from 3. The method of claim 1 or 2,
The oxycarboxylic acids are citric acid, tartaric acid, malic acid, gluconic acid, glucoheptonic acid, glycolic acid, lactic acid, trioxybutyric acid, ascorbic acid, isocitric acid, tartronic acid, glyceric acid, hydroxybutyric acid, leucine, citramalic acid , and at least one selected from the group consisting of salts thereof,
The aminocarboxylic acids are ethylenediaminetetraacetic acid, hydroxyethylethylenediaminetriacetic acid, diethylenetriaminepentaacetic acid, triethylenetetraminehexaacetic acid, ethylenediaminetetrapropionic acid, nitrilotriacetic acid, iminodiacetic acid, hydroxyethyl Iminodiacetic acid, iminodipropionic acid, 1,3-propanediaminetetraacetic acid, 1,3-diamino-2-hydroxypropanetetraacetic acid, glycol etherdiaminetetraacetic acid, metaphenylenediaminetetraacetic acid, 1,2-dia Minocyclohexane-N,N,N',N'-tetraacetic acid, diaminopropionic acid, glutamic acid, dicarboxymethylglutamic acid, ornithine, cysteine, N,N-bis(2-hydroxyethyl)glycine, (S, S)-ethylenediaminesuccinic acid, and at least one selected from the group consisting of salts thereof,
The polycarboxylic acid is at least one selected from the group consisting of succinic acid, glutaric acid, malonic acid, adipic acid, oxalic acid, maleic acid, citraconic acid, itaconic acid, mesaconic acid, and salts thereof. A copper colloidal catalyst solution for electroless copper plating. (a) an adsorption promoting step (pre-treatment) in which a non-conductive substrate is brought into contact with a liquid containing at least one adsorption accelerator selected from the group consisting of a nonionic surfactant, a cationic surfactant, an anionic surfactant, and an amphoteric surfactant process);
(b) a non-conductive substrate subjected to an adsorption promoting treatment is brought into contact with the copper colloidal catalyst solution for electroless copper plating according to claim 1 or 2 to adsorb the colloidal copper particles on the surface of the non-conductive substrate catalyst application process;
(c) an electroless plating step of forming a copper film using an electroless copper plating solution on the non-conductive substrate subjected to the catalyst application treatment;
A method of electroless copper plating comprising a. 7. The method of claim 6,
The electroless copper plating method characterized in that the adsorption accelerator used in the said adsorption acceleration process (a) contains at least a cationic surfactant. A method for producing a copper-plated substrate, wherein a copper film is formed on a non-conductive substrate by the electroless copper plating method according to claim 6 .