JP7204195B2 - Plating primer and laminate using the same - Google Patents

Description

The present invention relates to a plating base material and a laminate using the same.

The technology of forming metal plating (hereinafter simply referred to as "plating") on non-conductive substrates such as plastics, ceramics, glass, etc. , electromagnetic shielding, and wiring technology for printed circuit boards and large-scale integrated circuits.

A non-conductive substrate cannot obtain a metallic bond at the interface with the plating. Therefore, in order to plate a non-conductive base material, the surface of the non-conductive base material is chemically roughened (provided with fine irregularities) (etching) with chromic acid or the like, and the etched part is covered with palladium- Usually, a catalyst metal such as a tin complex is adsorbed (catalyst), a tin salt is dissolved, a metal palladium is produced by an oxidation-reduction reaction (accelerator), and then plated with nickel or the like. However, there is a problem that the pretreatment from etching to plating of the accelerator is complicated. In addition, it is necessary to use chemicals such as chromic acid, which have a high environmental impact, for the pretreatment, and there is also the problem that expensive palladium, which is a rare metal, is also required. Furthermore, there is also a problem that only ABS resin can be appropriately formed with fine unevenness by etching.

Patent Literatures 1 to 7 disclose techniques for plating a non-conductive base material by performing a treatment aimed at achieving the same effect as etching without using chromic acid. Patent Literatures 1 and 2 disclose a method of imparting an effect equivalent to the anchoring effect of etching by modifying the base material surface with laser or ozone. Patent Documents 3 and 4 disclose a method of forming an adhesive layer having binding properties with a catalyst on a substrate to generate chemical bonds between the substrate, the adhesive layer, and the catalyst, respectively. there is Patent Documents 5 to 7 disclose a method of forming an underlayer for electroless plating by coating a base material with a paint containing an electroless plating catalyst.

JP 2016-113688 A JP 2010-270389 A Japanese Patent Application Laid-Open No. 2010-031318 JP 2008-050541 A JP 2010-171045 A International publication 2015/045056 pamphlet Japanese Unexamined Patent Application Publication No. 2017-020118

However, Patent Documents 1 to 4 all describe a step of applying a catalyst between a pretreatment step for imparting adhesion and an electroless plating step (for example, palladium ions are attached to the substrate. A step of metallizing the palladium ions later to form a palladium metal serving as a catalyst) and a step of activating the catalyst metal are required. That is, the number of steps is the same as that of conventional etching using chromic acid, and the problem of complicated steps has not been resolved.

In Patent Document 5, before electroless plating, a reduction step using a boron-based compound and a cleaning step for removing the boron-based compound are required, called an activation step. When such a paint is used, there is a problem that the process becomes complicated.

In Patent Document 6, it is necessary to use nano-metal particles at a high ratio, and in Cited Document 7, it is necessary to use metal particles to which hyperbranched polymers are adhered, so there is a problem that both are expensive. In addition, with the spherical particles of Patent Documents 6 and 7, when deposited on the surface of the plating layer, the metal particles tend to slide down, resulting in deterioration of the plating bath.

An object of the present invention is to solve the above-mentioned problems, and to provide a base material and a laminate using the same, which can be performed in a simpler process and at a lower cost than the conventional plating pretreatment. It is intended for

The present inventors have found that the above object can be achieved by using a dispersion obtained by mixing a dispersion of nanowires and a dispersion of a water-insoluble resin having a hydrophilic group as a plating base material, and have reached the present invention. .

That is, the gist of the present invention is as follows.
(1) A plating base material containing a dispersion of nanowires and a water-insoluble resin having a hydrophilic group, wherein the nanowires are nickel nanowires .
(2) The mass ratio of the nanowire and the water-insoluble resin having a hydrophilic group (nanowire/water-insoluble resin having a hydrophilic group) is 20/80 to 30/70. Plating base agent described.
(3) The plating base agent according to (1) or (2) , wherein the hydrophilic group of the water-insoluble resin is an acidic functional group.
(4) The plating base agent according to any one of (1) to (3) , wherein the water-insoluble resin is a polyolefin resin.
(5) The plating base agent according to any one of (1) to (4) , which further contains a cross-linking agent.
(6) The plating base agent according to (5) , wherein the cross-linking agent is an oxazoline compound.
(7) A laminate comprising a non-conductive material and a plating base layer made of a mixture of nanowires and a water-insoluble resin having a hydrophilic group, wherein the nanowires are nickel nanowires .
(8) A laminate comprising a plating layer further provided on the plating base layer of the laminate of (7) .
(9) The laminate according to (8) , wherein the plating layer is nickel.
(10) The laminate according to (9) , wherein the nickel of the plating layer is nickel obtained by electroless plating.
(11) The laminate according to any one of (7) to (10) , wherein the water-insoluble resin has a three-dimensional network structure with a portion of the hydrophilic groups serving as crosslinking points.
(12) A method for producing a laminate, which comprises coating or printing the plating base material according to any one of (1) to (6) on a non-conductive material, followed by plating.
(13) The method for producing a laminate according to (12) , wherein the plating treatment is electroless plating.

By using the plating base material of the present invention, a plating layer can be provided simply by coating or printing a non-conductive material and immersing it in a plating solution. In addition, plating can be performed at low cost.
Further, since the plating underlayer formed using the plating underlayer of the present invention is insoluble in the plating solution, the plating bath is less likely to be contaminated even when the material provided with the plating underlayer is immersed.
Furthermore, since the plating underlayer is composed of nanowires and a water-insoluble resin, when the plating underlayer is provided, there are portions where the nanowires are exposed on the surface of the plating underlayer and portions where the nanowires are buried in the resin. The exposed portion of the nanowire becomes the starting point of plating, and the buried portion exerts the effect of enhancing the adhesion of the plating, so that a plating layer with excellent adhesion can be formed.

The plating underlayer of the present invention contains a dispersion of nanowires and a water-insoluble resin having a hydrophilic group.

(nanowire)
In the present invention, by using nanowires, an exposed portion and a buried portion are formed when the plating underlayer is provided, so that the adhesion to the plating layer is high.

The nanowire used in the present invention is a conductive fibrous substance having a diameter of about 30 to 200 nm and a length of about 1 to 50 μm. In the present invention, it is preferable to have a diameter of about 60 to 150 nm and a length of about 10 to 40 μm. By setting the diameter and length in the above ranges, the dispersibility of the nanowires is improved, and furthermore, the plating layer It is possible to improve the adhesion with.

The nanowires are preferably nanowires made of semiconductors, metals, metal oxides, or the like. Among these, nanowires made of metal are preferable because they tend to serve as starting points for plating when performing electroless plating. Although the type of metal is not particularly limited, examples thereof include nanowires of nickel, copper, and silver. A nanowire may be used independently and may use 2 or more types together.

When electroless plating is applied, a noble metal having a high oxidation-reduction potential such as platinum or palladium is usually used as a catalyst metal serving as a starting point for plating. On the other hand, in the present invention, plating grows starting from a portion of the nanowires exposed on the surface, so even metals with a low oxidation-reduction potential can grow plating. Specifically, metals with a standard oxidation-reduction potential of −0.8 V or more can grow plating. Therefore, in the present invention, even relatively inexpensive base metals can be used. Since nickel is often used in electroless plating, nickel is preferable as the metal because it improves adhesion to the plating layer.

In the present invention, even if the nanowires are metal oxide nanowires, electroless plating can be applied as in the case of using metal nanowires. Since the plating solution usually contains a reducing agent, the reducing agent reduces part of the nanowires exposed on the surface of the plating underlayer, and the plating grows from these as starting points.

The content of the nanowires in the plating underlayer is not particularly limited as long as the nanowires can be partly exposed on the surface of the underlayer. When the base layer is formed by general die coating, dip coating, screen printing, etc., by setting the content of the nanowires to 0.01 to 40% by mass, part of the nanowires can be exposed on the surface of the base layer. can.

(Water-insoluble resin having hydrophilic group)
The resin used in the present invention must be water-insoluble. In the present invention, water-insoluble means that the solubility in water at 25° C. is less than 1 g/100 g-H ₂ O. If the resin to be used is water-soluble, when the material provided with the underlayer on the surface is immersed in the plating solution, the underlayer dissolves, contaminating the plating bath, which is not preferable.

Examples of water-insoluble resins include polyolefin resins, polyester resins, polyamide resins, polyurethane resins, polyacrylic resins, and fluororesins. Among them, polyolefin resins are preferred. A single resin may be used, or two or more resins may be used in combination. Examples of polyolefin-based resins include ethylene homopolymers such as low-, medium-, and high-density polyethylene (branched or linear); ethylene-propylene copolymers, ethylene-1-butene copolymers, ethylene-4- Methyl-1-pentene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, ethylene-vinyl alcohol copolymer (including ethylene-vinyl acetate copolymer saponified product), ethylene - Ethylene-based resins such as (meth)acrylic acid copolymers; propylene homopolymers; propylene-based resins such as ethylene copolymers and propylene-ethylene-1-butene copolymers; 1-butene homopolymers, 1-butene-ethylene copolymer, 1-butene-based resin such as propylene copolymer; ring-opening metathesis polymer of norbornene, norbornene derivative-so-called cyclic polyolefin resin such as ethylene copolymer; ethylene- Propylene-butene-maleic anhydride copolymer, ethylene-(meth)acrylic acid ester-maleic anhydride copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-maleic anhydride copolymer, propylene-anhydride Acid-modified polyolefin resins such as maleic acid copolymers, ethylene-propylene-maleic anhydride copolymers, ethylene-butene-maleic anhydride copolymers, propylene-butene-maleic anhydride copolymers can be mentioned.

Moreover, the resin used in the present invention must have a hydrophilic group. In the present invention, the term "hydrophilic group" means an atomic group that forms a bond with a water molecule through electrostatic action, hydrogen bonding, or the like, and becomes stable in water. Hydrophilic groups improve wettability, making it difficult to repel the plating solution, and the gas generated when the plating layer is formed does not stay on the surface of the base layer and can easily escape, forming a uniform plating layer. can do. The hydrophilic group improves the dispersion stability of the resin in the plating undercoat, and when a cross-linking agent is added, the hydrophilic group can be used as a cross-linking point to form a three-dimensional network structure. preferable.

Examples of acidic functional groups include carboxyl groups, carboxylic anhydride groups, sulfonic acid groups, sulfinic acid groups, sulfenic acid groups, phosphoric acid groups, and phosphonic acid groups. An acid group is preferable, and a carboxyl group and a carboxylic anhydride group are more preferable from the viewpoint of adhesion to the plating layer. The resin may have one or more functional groups. Moreover, the functional group may form a salt. The content of hydrophilic groups in the resin is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and further preferably 0.5 to 20% by mass. ∼15% by mass is particularly preferable, and 1.5 to 10% by mass is most preferable. If the content of the acidic functional group is less than 0.1% by mass, the adhesion to the plating layer may be low.

In the present invention, the water-insoluble resin having a hydrophilic group is dispersed (emulsified, emulsified) in the plating undercoat without dissolving in the dispersion medium.

The content of the resin in the plating undercoat is preferably 0.1 to 5.0% by mass, more preferably 0.1 to 1.0% by mass, because the dispersed state is easily maintained. is more preferred.

(mass ratio of nanowires and resin)
The mass ratio of nanowires and resin (nanowires/resin) in the plating undercoat is easy to expose part of the nanowires on the surface of the underlayer, and the adhesion to the plating layer is high, so it is 20/80-. It is preferably 30/70, more preferably 25/75 to 30/70.

(dispersion medium)
The plating base material of the present invention contains a highly polar solvent and water as a dispersion medium. Alcohol, glycol, etc. are mentioned as a solvent with high polarity. Among them, a dispersion medium containing water as a main component is preferable. The dispersion medium may contain an organic solvent or a basic compound used for promoting the dispersion of the resin.

The content of the dispersion medium in the plating undercoat is not particularly limited as long as the state in which the resin is dispersed can be maintained. For example, if the resin is a polyolefin resin, the content is preferably 10% by mass or more, more preferably 30% by mass or more.

(crosslinking agent)
The plating underlayer of the present invention preferably contains a cross-linking agent in order to improve the chemical resistance and thermal resistance of the underlayer. The cross-linking agent may be either a water-soluble cross-linking agent or a water-insoluble cross-linking agent. Even when a water-soluble cross-linking agent is used, the cross-linking reaction proceeds by drying after coating, and the material becomes insoluble in water. The cross-linking agents may be used alone or in combination of two or more. The cross-linking agent can be appropriately selected according to the resin to be used. Examples of cross-linking agents include oxazoline compounds, carbodiimide compounds, epoxy compounds, and isocyanate compounds, and oxazoline compounds are preferred from the viewpoint of reactivity and pot life.

(Additive)
The plating base material of the present invention may contain additives such as antifoaming agents, rheology control agents, wetting agents, leveling agents, etc., to the extent that the effects of the invention are not impaired.

(Manufacturing method of plating undercoat)
Although the method for producing the plating undercoat of the present invention is not particularly limited, for example, a method of producing a nanowire dispersion and a resin dispersion and mixing the dispersions can be mentioned. The method for mixing the dispersion is not particularly limited, and for example, a method of adding the nanowire dispersion to the resin dispersion while stirring, or a method of adding the resin dispersion to the nanowire dispersion while stirring. method.

(Method for producing nanowire dispersion)
The method for producing the nanowire dispersion used in the present invention is not particularly limited, but in the case of nickel nanowires, for example, a method of producing by reducing nickel ions in a reaction solvent with a reducing agent in a magnetic circuit. are mentioned. According to the method, nickel nanowires in which nickel nanoparticles are uniaxially connected can be efficiently manufactured.

Nickel ion sources include, for example, chlorides, sulfates, nitrates, and acetates of nickel. The concentration of the metal ions to be reduced is preferably 1.5 to 20 μmol/g, more preferably 1.5 to 15 μmol/g, with respect to the reaction solution from the viewpoint of nanowire shape control. It is preferably 1.5 to 10 μmol/g, more preferably 1.5 to 10 μmol/g.

Examples of reducing agents include hydrazine, hydrazine monohydrate, ferrous chloride, hypophosphorous acid, borohydride salts, aminoboranes, lithium aluminum hydride, sulfites, hydroxylamines (e.g., diethylhydroxylamine ), zinc amalgam, diisobutylaluminum hydride, hydroiodic acid, ascorbic acid, oxalic acid, formic acid, ferrous chloride, hypophosphorous acid, borohydride salts, aminoboranes, ascorbic acid, oxalic acid, and formic acid. Among them, hydrazine and hydrazine monohydrate are preferable because of their high reduction efficiency. When hydrazine monohydrate is used as the reducing agent, the concentration of addition is preferably 0.05 to 1.0% by mass relative to the reaction solution.

Polyols such as ethylene glycol and propylene glycol are preferable as the reaction solvent. Polyols are capable of dissolving metal salts (particularly nickel salts) and reducing agents, and boiling does not occur even at the reaction temperature, so that the reaction can be performed with good reproducibility.

It is preferable to control pH and temperature to reduce nickel ions. The optimum pH and temperature vary depending on the reducing agent. For example, when hydrazine monohydrate is used for the reduction reaction, the temperature is preferably 70 to 100° C., and the pH is 11 to 12. is preferred.

As for the magnetic field applied when reducing metal ions, the central magnetic field of the reaction vessel is preferably 10 to 200 mT, more preferably 80 to 180 mT. A weak magnetic field may not generate nanowires, and a strong magnetic field is difficult to generate, making it impractical.

In order to control the average diameter and average length of nanowires, a nucleating agent may be added to the reaction solution depending on the type of metal ions to be reduced and the reducing agent. Nucleating agents include, for example, salts of noble metals such as gold, silver, platinum, palladium, rhodium, iridium, ruthenium, and osmium. Specific examples of the noble metal salt include chloroplatinic acid, chloroauric acid, and palladium chloride, among which salts of platinum are preferred, and chloroplatinic acid is more preferred. The amount of the nucleating agent is preferably 5,000 to 10,000,000 moles, more preferably 10,000 to 1,000,000 moles of metal ions to be reduced with respect to 1 mole of noble metal ions of the nucleating agent.

The reduction time of the reduction reaction is not particularly limited as long as nanowires can be produced, but it is usually 10 minutes to 1 hour, preferably 10 minutes to 30 minutes. After that, the nanowires can be isolated by purifying and recovering the nanowires by centrifugation, filtration, magnetic adsorption, or the like.

The nanowires isolated by the above production method can be mixed with a dispersion medium to adjust the solid concentration of the dispersion to a desired concentration.

(Method for producing resin dispersion)

The method for producing the dispersion of the water-insoluble resin having a hydrophilic group used in the present invention is not particularly limited. A method of heating and stirring with According to the above method, a resin dispersion can be efficiently obtained without substantially adding an emulsifier component or a non-volatile water-forming aid such as a compound having a protective colloid action.

Any vessel may be used as long as it has a tank into which a liquid can be introduced and can moderately stir the mixture of the medium (liquid) and the resin introduced into the tank. As such a device, a device widely known to those skilled in the art as a solid/liquid stirring device or an emulsifier can be used, and it is preferable to use a device capable of applying a pressure of 0.1 MPa or more. In the present invention, the method of stirring and the rotation speed of stirring are not particularly limited, but sufficient dispersion can be achieved even with low-speed stirring that causes the resin to float in the medium, and high-speed stirring (e.g., 1000 rpm or more) is essential. is not. Therefore, even a simple apparatus can produce a dispersion liquid.

A medium selected from water, a basic compound, an organic solvent, etc., which is used as necessary, and a resin are put into the tank of this apparatus, and stirred and mixed preferably at a temperature of 40° C. or lower. Next, while maintaining the temperature in the tank at 70 to 210° C., preferably 80 to 180° C., more preferably 90 to 150° C., stirring is preferably continued for 5 to 120 minutes to sufficiently disperse the resin. and then cooled to 40° C. or lower, preferably with stirring, to obtain a stable dispersion. If the temperature in the tank is less than 70°C, the resin may not be sufficiently dispersed. If the temperature in the tank exceeds 210°C, the molecular weight of the resin may decrease. As a method for heating the inside of the tank, heating from the outside of the tank is preferable. For example, heating using oil or water, or heating by attaching a heater to the tank can be performed. As a method for cooling the inside of the tank, for example, a method of naturally cooling at room temperature or a method of cooling using oil or water at 0 to 40°C can be mentioned.

The resulting resin dispersion can be adjusted to a desired solid concentration by, for example, distilling off the dispersion medium or diluting the dispersion.

By the above method, a resin dispersion is obtained by dispersing the resin in a dispersion medium and preparing a uniform liquid. Here, the term “uniform liquid” means that the dispersion is in a state in which there is no local difference in solid content concentration from other portions, such as precipitation, phase separation, or skinning, in appearance. means.

Regarding the dispersed particle size of the resin, the number average particle size is preferably 1 μm or less, more preferably 0.8 μm or less, from the viewpoint of stability when mixed with other components and storage stability after mixing. preferable. Incidentally, the number average particle size of the resin can be measured by a dynamic light scattering method.

(Laminate)
By coating or printing the plating base material of the present invention on a non-conductive material, a laminate having a plating base layer made of a mixture of nanowires and a water-insoluble resin having a hydrophilic group on the surface can be obtained. can. The shape of the non-conductive material to be coated or printed is not particularly limited, but it may be a three-dimensional molded product as well as a film.

The coating method is not particularly limited, and can be appropriately selected according to the shape of the non-conductive material to be coated. For example, film coating methods include die coating, and three-dimensional molding coating methods include dip coating and spray coating.

The printing method is not particularly limited, and can be appropriately selected according to the shape of the non-conductive material to be printed. Examples of methods for printing films include flexographic printing and gravure printing, and examples of methods for printing three-dimensional moldings include inkjet printing and soft blanket gravure printing.

A laminate having a plating underlayer on a non-conductive material can be obtained by immersing the laminate in a plating solution and drying to obtain a laminate having a plating layer. The plating method is not particularly limited, but electroless plating is preferred because plating can be performed regardless of the conductivity of the plating undercoat. Whether or not nickel is obtained by electroless plating can be determined by whether or not the plated layer contains phosphorus or boron. If the plated layer contains phosphorus or boron, it is obtained by electroless plating. In addition, in the present invention, by increasing the mass ratio of nanowires and resin (nanowires/resin), the plating underlayer becomes conductive, so electrolytic plating can also be applied.

A printed circuit board can be obtained by using the substrate as the non-conductive material in the laminate. By using the above method, it is possible to plate only the printed portion. Moreover, by using the above method, a printed circuit board can be obtained at a lower cost than the conventional method of forming a printed circuit board by etching.

Non-conductive materials and non-conductive substrate materials coated or printed with the plating undercoat of the present invention include, for example, polypropylene, polyethylene, polystyrene, polyurethane, polyvinyl chloride, polyethylene terephthalate, polyacetal, polyamide, polycarbonate, and polyphenylene ether. , polyphenylene sulfide, polyimide, liquid crystal polymer, epoxy resin, phenolic resin and other resin materials, composite materials composed of resin materials and inorganic fillers, glass, and ceramics.

EXAMPLES The present invention will be specifically described below with reference to Examples, but the present invention is not limited to these. In addition, evaluation of the plating base agent was performed by the following methods.

A. Evaluation Method (1) Plating Precipitation PET film was cast-coated with the plating base material prepared in Examples and Comparative Examples and dried at 100° C. to obtain a PET film having a base layer on the surface.
The obtained PET film provided with the underlayer was immersed in an electroless nickel plating solution (Top Nicolon XT-LF manufactured by Okuno Chemical Industry Co., Ltd.) heated to 90° C. for 60 minutes, picked up, dried, and plated on the surface. A layered PET film was obtained.
The resulting PET film provided with a plating layer was visually observed, and the depositability of plating was evaluated according to the following criteria.
A: A uniform and smooth plating layer was obtained.
◯: A plated layer that was uniform but had unevenness was obtained.
x: Deposition of plating was partial, and there was dropout of the plating layer.
XX: No plating was deposited.

(2) Contamination of Plating Bath After the PET film provided with the underlying layer obtained in (1) was taken out of the plating bath, the contamination of the plating bath was evaluated according to the following criteria.
◯: Metal was deposited only on the PET film.
x: Precipitation of the metal was observed also at locations other than the PET film. (Metal was deposited on the bottom and walls of the plating bath.)

(3) Adhesion of plating A cellophane tape is attached to the PET film provided with the plating layer obtained in (1), and the adhesion to the plating layer is evaluated by the ratio of the peeled area to the area where the cellophane tape is attached. bottom.
◎: Less than 1% ○: 1% or more and less than 99% ×: 99% or more

B. Materials (1) Oxazoline compound A: Oxazoline group-containing polymer, Epocross WS700 manufactured by Nippon Shokubai Co., Ltd.
(2) Water-soluble polymer A: Polyvinylpyrrolidone, Pitzcol K90 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.
(3) Nickel particles: Nickel powder Type 123 manufactured by Vale

Example 1
(Preparation of aqueous dispersion of nickel nanowires)
0.25 g (1.05 mmol) of nickel chloride hexahydrate was added to ethylene glycol for a total weight of 50 g. This solution was heated to 90° C. to dissolve the nickel chloride. On the other hand, 0.40 g of sodium hydroxide and 30.7 μg (59.4 nmol) of chloroplatinic acid hexahydrate were added to ethylene glycol to make the total amount 49.9 g. This solution was heated to 90° C. to dissolve sodium hydroxide and chloroplatinic acid. After all the compounds in each solution were dissolved, 0.1 g of hydrazine monohydrate was dissolved in the solution containing sodium hydroxide and then the two solutions were mixed. The mixed solution was immediately placed in a magnetic circuit capable of applying a magnetic field of 150 mT to the center, and the magnetic field was applied, and the solution was allowed to stand still for 15 minutes while the temperature was maintained at 90 to 95° C. to carry out a reduction reaction. After the reduction reaction, the nanowires were collected with a neodymium magnet. The nanowires obtained had an average length of 20 μm and an average diameter of 91 nm. The nanowires and water were mixed to prepare an aqueous dispersion of nickel nanowires having a solid concentration of 1.0% by mass.

(Preparation of aqueous dispersion of polyolefin resin)
280 g of a propylene/butene/ethylene terpolymer (mass ratio: propylene/1-butene/ethylene = 64.8/23.9/11.3) was heated and melted in a four-necked flask under a nitrogen atmosphere. let me After that, while maintaining the temperature in the system at 170° C., 32 g of maleic anhydride and 6 g of dicumyl peroxide were each added over 1 hour while stirring, and then reacted for 1 hour. After completion of the reaction, the obtained reactant was put into a large amount of acetone to precipitate a resin. This resin was further washed with acetone several times to remove unreacted maleic anhydride and then dried under reduced pressure to synthesize a polyolefin resin composed of an acid-modified propylene/butene/ethylene terpolymer. Subsequently, using a stirrer equipped with a heater-equipped sealable pressure-resistant 1 L glass container, 45.0 g of the above polyolefin resin, 105.0 g of tetrahydrofuran, 3.0 g of cyclohexane, 9.0 g of dimethylaminoethanol and 138.0 g of distilled water was charged into a glass vessel and stirred with a stirring blade rotating at 300 rpm. While maintaining this state, the heater was turned on to heat, and the temperature in the system was kept at 125° C. and stirred for 60 minutes. After that, the mixture was cooled to room temperature (about 25° C.) while stirring in a water bath, and 80.0 g of distilled water was added. The resulting dispersion was placed in a 1-L eggplant flask, and the pressure was reduced using an evaporator while being placed in a hot water bath heated to 60° C. to distill off 155.0 g of the medium. After cooling, the liquid component in the flask was pressure-filtered (air pressure 0.2 MPa) through a 300-mesh stainless steel filter (wire diameter 0.035 mm, plain weave) to obtain a milky-white uniform polyolefin-based solid content concentration of 20% by mass. An aqueous dispersion of the resin was prepared.

(Preparation of plating base agent)
To 810 parts by mass of the aqueous dispersion of nickel nanowires, 100 parts by mass of the aqueous dispersion of polyolefin resin was gradually mixed with stirring so that the total solid content of the nanowires and the polyolefin resin was 0.73. % to prepare a plating undercoat.
The mass ratio (nanowire/polyolefin resin) of metal and resin in the plating undercoat was 29/71.

Example 2
To 810 parts by mass of the aqueous dispersion of nickel nanowires prepared in Example 1, 100 parts by mass of the aqueous dispersion of polyolefin resin prepared in Example 1 and 10 parts by mass of oxazoline compound A were gradually mixed with stirring to obtain a nano The wire, the polyolefin resin, and the oxazoline compound A were diluted with water so that the total solid content was 0.73% to prepare a plating base material.
The mass ratio (nanowire/polyolefin resin) of metal and resin in the plating undercoat was 29/71.

Example 3
A plating underlayer was prepared in the same manner as in Example 2, except that the mass ratio of the aqueous dispersion of nickel nanowires was changed as shown in Table 1.

Comparative example 1
A 20% by mass aqueous solution was prepared by dissolving the water-soluble polymer A in water.
810 parts by mass of the nickel nanowire aqueous dispersion prepared in Example 1 was gradually mixed with 100 parts by mass of the aqueous solution of the water-soluble polymer A while stirring until the total solid content of the nanowires and the water-soluble polymer A was 0. The solution was diluted with water to a concentration of 73% to prepare a plating undercoat.
The mass ratio (nanowire/water-soluble polymer A) of metal and resin in the plating undercoat was 29/71.

Comparative example 2
The aqueous dispersion of nickel nanowires prepared in Example 1 was diluted with water to a solid content of 0.73% to prepare a plating undercoat.

Comparative example 3
The aqueous dispersion of the polyolefin-based resin prepared in Example 1 was diluted with water so that the solid content was 0.52% to prepare a plating undercoat.

Comparative example 4
Nickel particles were mixed with water to prepare an aqueous dispersion of 1.0% by mass of nickel particles.
To 200 parts by mass of the aqueous dispersion of nickel particles, 100 parts by mass of the aqueous dispersion of the polyolefin resin prepared in Example 1 and 10 parts by mass of the oxazoline compound A were gradually mixed with stirring to obtain the nickel particles, the polyolefin resin and the oxazoline. The compound A was diluted with water so that the total solid content was 0.73% to prepare a plating undercoat.
The mass ratio (nickel particles/polyolefin resin) of the metal and the resin in the plating undercoat was 51/49.

Comparative Examples 5 and 6
Except for changing the mass ratio of the aqueous dispersion of nickel particles as shown in Table 1, the same operation as in Comparative Example 4 was performed to prepare a plating undercoat.

Table 1 shows the formulations of the plating undercoating agents and the evaluation results of the laminates obtained in Examples and Comparative Examples.

In Examples 1 to 3, a dispersion of nanowires and a water-insoluble resin having a hydrophilic group was used as the plating undercoat, so a uniform plating layer could be obtained simply by immersion in the plating solution. Moreover, the plating bath was not contaminated, and the formed plating layer was uniform and had high adhesion.
From the comparison between Example 1 and Example 2, it can be seen that the adhesion of the formed plating layer is higher when the plating base material contains the cross-linking agent.
From the comparison of Example 2 and Example 3, the mass ratio of nanowires/resin (nanowires/resin) was 20/80 to 30/70, so that the formed plating layer has higher adhesion. .

In Comparative Examples 1 and 2, since no water-insoluble resin was added, the plating layer fell off and the plating was uneven. In addition, the nickel nanowires and the like that fell out contaminated the plating bath, and metal was deposited on the base material other than the base material to which the plating primer was applied.
In Comparative Example 3, a dispersion liquid containing only a water-insoluble resin was used as the plating undercoat, and thus a plating layer was not formed even when immersed in the plating liquid.
In Comparative Example 4, since nickel particles were used, the depositability of the plating was poor.
In Comparative Example 5, since nickel particles were used, the adhesion of the plating underlayer itself was low, and the underlayer peeled off during the plating process. Moreover, the deposition of the plating was partial, and the plating layer fell off. In addition, the plating bath was contaminated by fallen nickel particles and the like, and metal was deposited on the base material other than the base material coated with the plating primer.

Claims (13)

containing a dispersion of nanowires and a water-insoluble resin having a hydrophilic group ;
A plating primer, wherein the nanowires are nickel nanowires . The plating according to claim 1, wherein the mass ratio of the nanowires and the water-insoluble resin having a hydrophilic group (nanowires / water-insoluble resin having a hydrophilic group) is 20/80 to 30/70. grounding agent. 3. The plating primer according to claim 1, wherein the hydrophilic group of the water-insoluble resin is an acidic functional group. 4. The plating base material according to any one of claims 1 to 3 , wherein the water-insoluble resin is a polyolefin resin. 5. The plating base material according to any one of claims 1 to 4 , further comprising a cross-linking agent. 6. The plating primer according to claim 5 , wherein the cross-linking agent is an oxazoline compound. 1. A laminate comprising a non-conductive material and a plating base layer comprising a mixture of nanowires and a water-insoluble resin having a hydrophilic group, wherein the nanowires are nickel nanowires . 8. A laminate comprising a plating layer further provided on the plating base layer of the laminate according to claim 7 . 9. The laminate according to claim 8 , wherein the plated layer is nickel. 10. The laminate according to claim 9 , wherein the nickel of the plated layer is nickel obtained by electroless plating. 11. The laminate according to any one of claims 7 to 10 , wherein the water-insoluble resin has a three-dimensional network structure with a portion of the hydrophilic groups serving as cross-linking points. A method for producing a laminate, which comprises coating or printing the plating base material according to any one of claims 1 to 6 on a non-conductive material, followed by plating. 13. The method for producing a laminate according to claim 12 , wherein the plating treatment is electroless plating.