JP2010031306A - Method of plating on resin base material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of plating on a resin base material by which a smoothed plated surface is obtained even on the roughened surface of the resin base material without etching as a pretreatment step. <P>SOLUTION: The method of plating on the resin base material at least includes: a step S12 of carrying out an ozone water treatment on the surface of the resin base material having unsaturated bond; a step S14 of carrying out a catalyst adsorption treatment of adsorbing a metal catalyst on the treating surface; a step S15 of carrying out electroless plating treatment on the treating surface after catalyst adsorption treatment; a first electroplating treatment step S16 of carrying out semi-lustrous metal plating treatment on the treating surface after electroless plating treatment so that the center line average surface roughness Ra becomes 0.1-0.5 μm; and a second electroplating treatment step S17 of carrying out lustrous metal plating treatment on the treating surface after the first electroplating treatment so that the center line average surface roughness Ra becomes ≤0.03 μm. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is a method for performing plating treatment on the surface of a resin substrate, and plating treatment on a resin substrate capable of obtaining a smooth plating treatment surface without performing etching treatment as a base treatment of the resin substrate. Regarding the method.

  Conventionally, when a metal plating film is formed on a surface of a polymer resin so as to impart conductivity and gloss, plating treatment is often performed. As this plating treatment, a metal film is formed on the surface of the polymer resin by chemically reducing and precipitating metal ions in the solution on the surface of the non-conductive resin that is the base of the resin substrate (nothing) Electrolytic plating treatment) may be performed.

  Since the electroless plating process uses a chemical reduction reaction, a metal film (metal plating) is generally used even on the surface of a polymer resin made of an insulator, unlike electroplating in which electric field deposition is performed by electric power. Layer) can be formed. Next, electroplating is performed on the surface of the metal coating to improve not only the strength of the metal coating but also the design.

  For example, as a plating method for such a resin substrate, (1) a step of etching the surface of the resin substrate with chromic acid, and (2) a catalyst for adsorbing a metal catalyst on the treated surface after the etching treatment A step of performing adsorption treatment; (3) a step of performing electroless plating treatment on the treated surface after the catalyst adsorption treatment; and (4) performing semi-gloss metal plating treatment on the treated surface after the electroless plating treatment. There has been proposed a plating method including at least a step and (5) a step of performing a bright metal plating treatment on the treated surface after the first electroplating step (see, for example, Patent Document 1).

  According to such a plating method for a resin base material, a smooth plating-treated surface without roughness can be obtained by performing a series of plating treatments on the surface after the etching treatment.

JP 2007-39770 A

  However, in the etching treatment with chromic acid, the roughness of the surface of the resin substrate is dissolved by chromic acid, whereby the substrate is smoothed. This chromic acid contains hexavalent chromium. The use of hexavalent chromium is not desirable from the viewpoint of environmental characteristics including the working environment.

  From such a viewpoint, in recent years, ozone water treatment may be performed on the surface of the resin base material as an alternative process of the etching treatment shown in (1) above. By performing this ozone water treatment, the surface layer of the resin base material is modified without dissolving the surface of the resin base material, thereby improving the adsorptivity of the metal catalyst and obtaining a plating film with high adhesion. be able to.

  By the way, the resin convex part of 10-500 micrometers exists in the surface of the resin base material shape | molded by injection molding. However, ozone and hydroxy radicals, which are active species in ozone water, have a very short lifetime, and thus are deactivated before deeply penetrating into the plating resin. Therefore, as shown in FIG. 3, the resin surface is hardly smoothed by the ozone water treatment, and the convex portions of the resin of 10 to 500 μm still remain on the treated surface after the ozone water treatment. For example, even when a series of plating treatments described in Patent Document 1 are performed on such a surface, plating is uniformly deposited on the surface of the resin. A convex part of 500 μm is formed.

  In addition, the semi-gloss metal plating process and the bright plating process described in Patent Document 1 are not treatments for smoothing the surface, as is apparent from the etching process performed in the previous step. . In other words, the essential part of the semi-gloss metal plating process and the bright plating process is not a process for improving the initial appearance of the plating, but for the purpose of suppressing the progress of corrosion in the layer thickness direction on the plating film. Focusing on the porous (microporous) structure of the layer, the plating layer is quasi-corroded. Therefore, even if a series of plating treatments described in Patent Document 1 are performed on the surface after the ozone water treatment, the occurrence of convex portions cannot be essentially avoided.

  The present invention has been made in view of the problems described above, and the object of the present invention is to perform smooth etching even on the surface of a resin substrate having roughness without performing an etching process as a pretreatment process. It is providing the plating processing method of the resin base material which can obtain the plating processing surface.

  In order to solve the above problems, a resin plating method for a resin base material according to the present invention includes a step of performing ozone water treatment on a treated surface of a resin base material having an unsaturated bond, and a metal catalyst on the treated surface. A center line average roughness Ra is 0.1 on the treatment surface after the catalyst adsorption treatment, the treatment surface after the catalyst adsorption treatment, the electroless plating treatment on the treatment surface after the catalyst adsorption treatment, and the treatment surface after the electroless plating treatment. The center line average roughness Ra is 0.1 on the first electroplating treatment step for performing the semi-gloss metal plating treatment and the treatment surface after the first electroplating treatment step so as to be in the range of ˜0.5 μm. It includes at least a second electroplating treatment step for performing a bright metal plating treatment so as to be in a range of 03 μm or less.

  According to the present invention, even if there are convex portions (pits) that cause roughness on the surface of the resin base material during molding, the center line average roughness Ra is set to 0. 1 in the first electroplating process. A semi-gloss metal plating process in the range of 1 to 0.5 μm is performed, and in the second electroplating process, the bright metal plating is performed so that the center line average roughness Ra is in a range of 0.03 μm or less. As a result, the plating surface is smoothed regardless of the protrusions on the surface of the resin substrate.

  Specifically, by performing a semi-gloss metal plating treatment in the range of the roughness, a plating treatment surface having fine irregularities that does not depend on the shape of the convex portions on the surface of the resin base material is formed, By performing the bright metal plating treatment within the roughness range, the plating treatment surface having the unevenness is leveled and the surface is smoothed.

  That is, in the first electroplating treatment step, when the center line average roughness Ra is less than 0.1 μm, the shape of the convex portion on the surface of the resin substrate appears on the plating treatment surface, and the second Even in the case of performing bright metal plating in the electroplating process, the surface of the plating process is difficult to be flattened. Further, in the first electroplating process, when the center line average roughness exceeds 0.5 μm, the shape of the convex portion on the surface of the resin base material does not appear on the plated surface, but it is semi-glossy. Due to the metal plating process itself, the surface of the plating process becomes uneven, and in this case as well, the surface of the plating process is hardly flattened.

  Further, even when the treated surface after the first electroplating treatment step is within the range of the surface roughness, when the center line average roughness Ra exceeds 0.03 μm, the plating is performed. The beauty of the treated surface is difficult to obtain.

  The semi-gloss metal plating process in the first electroplating process is a plating bath having a lower level electrodeposition (short Wagner length) and lower leveling action than the bright metal plating process. Examples thereof include a Watt nickel bath or a zinc sulfate bath to which a leveling agent smaller than the amount generally added conventionally is added.

  The bright metal plating process in the second electroplating process is a plating bath that has a higher level of electrodeposition and a higher leveling action than the semi-gloss metal plating process. And a copper sulfate bath to which a leveling agent greater than the amount added is added.

  Here, the uniform electrodeposition refers to geometric leveling, and the higher the uniform electrodeposition, the more a plating film is formed along the shape of the substrate. The leveling action generally means smoothing the surface of the plating thickness distribution in the order of cm or less when referring to the uniform electrodeposition of plating, but in the order of μm or less as in the plating treatment of the present invention. When the plating thickness distribution on the surface unevenness is a problem, it means smoothing the surface of the order of μm. This is sometimes referred to as micro-thickness electrodeposition (micro-throwing power) versus macro-type electrodeposition.

  Moreover, when performing the semi-gloss metal plating treatment and the bright metal plating treatment, in order to adjust the surface roughness, it can be adjusted by changing the composition and additives of each plating treatment liquid, More preferably, as will be described later, the surface roughness is adjusted by adjusting the amount of the leveling agent added to each plating solution.

  Thus, the surface roughness of the treated surface can be easily adjusted by adjusting the leveling agent. In the plating method for the resin substrate according to the present invention, a leveling agent is added to the plating treatment liquid for the semi-gloss metal plating treatment and the bright metal plating treatment, and the plating solution for the semi-gloss metal plating treatment is: It is more preferable that the addition amount of the leveling agent is smaller than the plating solution for the bright metal plating treatment.

  In addition, the leveling agent as used in the field of this invention means the additive added to a plating bath (plating process liquid) for the purpose of expressing the leveling effect | action with respect to a plating process. This leveling agent is easily adsorbed to the convex portions on the surface of the plating film by diffusing into the plating solution. Thereby, since the polarization of the adsorbed portion becomes large (because the activation overvoltage increases), the electrodeposition property to the convex portion is suppressed, and the plating is deposited more in the concave portion of the plating film. As a result, the treated surface on which plating is deposited (plated film is formed) is smoothed.

  For example, nickel plating leveling agents include benzene sulfonic acid, naphthalene sulfonic acid, toluene sulfonamide, sodium saccharin, formaldehyde, chloral hydrate, coumarin, butynediol, thiourea, sodium lauryl sulfate, ethylene cyanohydrin, propylene. Examples include kill alcohol, quinoline, and pyridine.

  Examples of the leveling agent for copper cyanide plating include sodium selenite (0.5-2 g / l), lead acetate (0.01-0.5 g / l), and the like. Examples of leveling agents for copper sulfate plating include phenazine compounds, safranine compounds, polyalkyleneimines, thiourea derivatives, polyacrylic acid amides, azo dyes, and compounds having dithiocarbamic acid groups.

  Examples of the resin having an unsaturated bond for performing the plating treatment in the present invention include ABS resin, AS resin, PS resin, AN resin, epoxy resin, PMMA resin, polyimide resin, polyphenyl sulfide resin, and the like. it can.

  Examples of the metal catalyst to be adsorbed on the polymer resin include metal catalysts such as palladium, silver, cobalt, nickel, ruthenium, cerium, iron, manganese, and rhodium, and combinations thereof may be used. .

  Furthermore, examples of the plating material for performing electroless plating include copper and nickel, and are particularly limited as long as a metal plating layer is formed on the surface of the polymer resin by electroless plating. It is not a thing. However, a more preferable metal catalyst is a palladium catalyst, and a plating material for performing electroless plating is nickel. The palladium catalyst is excellent in the adsorptivity with respect to the above-mentioned resin, and is rich in versatility. When nickel is formed, it is preferable from the viewpoint of adhesion and the like.

  More preferably, in the plating treatment method to the resin substrate according to the present invention, the electroless plating treatment is an electroless nickel plating treatment, the semi-bright metal plating treatment is a semi-bright nickel plating treatment, and The bright metal plating process is a bright copper plating process.

  In this way, the electroless nickel plating and the semi-bright nickel plating treatment are applied to the plating treatment that constitutes the underlayer, and the bright copper plating treatment is further applied to the surface plating treatment, thereby forming the nickel plating layer as the underlayer. Since the (nickel plating film) corrodes before the copper plating layer (copper plating film), the appearance of the surface copper plating layer is not impaired.

  Furthermore, in the plating method for the resin base material according to the present invention, after such a plating process, a chromium plating process may be performed. Further, a halfway between the second electroplating process and the chromium plating process is performed. Bright nickel plating, bright nickel plating, and joule nickel plating may be sequentially performed.

  According to the present invention, by performing the chromium plating treatment, it is possible to obtain a film that has excellent surface aesthetics, hardly discolors in the atmosphere, and is harder and has a smaller friction coefficient than other plating films. Furthermore, nickel with a higher ionization tendency than copper can be preferentially corroded by the semi-bright nickel plating treatment, and the bright nickel having a low natural potential is preferentially given to the semi-bright nickel by the bright nickel plating treatment. Can be corroded. The Joule nickel plating treatment is a nickel plating treatment in which non-conductive particles are dispersed in the nickel plating. By this treatment, a microporous chrome plating film can be obtained in the chrome plating treatment.

  Furthermore, the plating treatment method to the resin base material according to the present invention further includes a step of performing an alkali treatment by bringing an alkali solution containing at least a surfactant into contact with the treatment surface after the ozone water treatment before the catalyst adsorption treatment step. May be included. According to the present invention, this alkali treatment step can enhance the adsorptivity of a catalyst such as palladium.

  According to the plating method according to the present invention, it is possible to obtain a smooth plated surface even on the surface of a resin substrate having roughness without performing an etching treatment as a pretreatment step on the surface of the resin equipment. it can.

  Below, with reference to drawings, it explains based on an embodiment of a plating processing method to a resin substrate concerning the present invention. FIG. 1 is a work flow diagram for explaining each step of the plating method according to the present embodiment, and FIG. 2 is a diagram for explaining a resin base material plated by the present embodiment.

  As shown in FIG. 1, the plating method according to the present embodiment is a plating method for coating a surface of a resin base material with a metal plating film, and includes the following steps.

  A forming step S11 for forming a base material (resin base material) from a resin having an unsaturated bond such as an ABS resin is performed. The molding method of the substrate is not particularly limited, and various molding methods such as compression molding, extrusion molding, blow molding and injection molding can be employed.

  Next, ozone water treatment process S12 is performed. In the ozone treatment step S12, at least the treatment surface (resin surface) of the substrate is brought into contact with ozone water (water in which ozone is dissolved) to modify the surface layer including the substrate surface serving as the treatment surface. It is considered that at least a part of the unsaturated bond on the surface of the substrate is cleaved by oxidation with ozone in the solution to generate an ozonide, a methylol group, a carbonyl group, or the like. Since this methylol group, carbonyl group, etc. are functional groups capable of forming a chemical bond with a metal atom, they strongly bond to the plating film formed by electroless plating described later, so that the adhesion strength between the plating film and the substrate should be improved. Can do.

  As a method of contacting ozone water with the treated surface of the substrate, ozone water may be applied to the treated surface of the substrate by spraying, or the substrate may be immersed in the ozone water. In the present embodiment, ozone water is used, but it is a solution in which ozone can be dissolved, and the solvent in which ozone is dissolved is not limited to water as long as it does not damage the substrate.

  Next, alkali treatment process S13 is performed. In this alkali treatment S13, an alkali solution containing at least a surfactant is brought into contact with the treated surface after the ozone water treatment. Surfactant is for improving the adsorption property of the palladium catalyst mentioned later, and can mention anionic surfactants, such as sodium lauryl sulfate. Examples of the alkali component of the alkali solution include sodium hydroxide, potassium hydroxide, lithium hydroxide, etc., and the surface of the resin base material is dissolved at the molecular level to remove the embrittled layer, and an alkali metal such as sodium. Can be applied to the treated surface. Furthermore, it is desirable to use a polar solvent as the solvent of the solution containing the surfactant and the alkali component, and water can be used as a representative. May be.

  Moreover, in order to make an alkaline solution contact with a resin base material, the method of immersing a resin base material in a solution like the ozone water treatment, the method of apply | coating a solution to the surface by spray etc., etc. can be mentioned. More preferably, after this step, neutralization treatment (pre-dip treatment) is performed with an acid such as hydrochloric acid. In the catalyst adsorption treatment step, which will be described later, the alkali treatment step can enhance the adsorption property of the palladium catalyst to the treatment surface. If the desired amount of palladium catalyst can be adsorbed, this alkali treatment step is performed. It may be omitted.

  Next, the catalyst adsorption processing step S14 is performed. In this catalyst adsorption treatment step S14, the treated surface treated with alkali is immersed in a catalyst solution (catalyzer) in which palladium chloride and tin chloride are dissolved in an aqueous hydrochloric acid solution. Thereby, a palladium catalyst is made to adsorb | suck to the process surface of a base material. Then, the treatment surface is brought into contact with an acidic solution to activate the palladium catalyst. Next, an electroless plating treatment step S15 is performed. In the electroless plating treatment step 15, a nickel plating solution is immersed in the treated surface after the catalyst adsorption treatment to deposit nickel on the surface, and as shown in FIG. An electroless nickel plating film is formed.

  Next, the first electroplating process S16 is performed. In the first electroplating treatment step S16, semi-gloss metal plating is performed on the treated surface after the electroless plating treatment so that the center line average roughness Ra is in the range of 0.1 to 0.5 μm.

  Specifically, compared to the later-described bright metal plating treatment, a Watt nickel bath in which the amount of leveling agent added is adjusted so that the throwing power is low (the Wagner length is short) and the leveling action is low. Then, the nickel electroplating is performed by energizing between the electrode in the bath and the electrolessly plated surface. In this way, by adjusting the leveling agent or the like so that the center line average roughness Ra is in the range of 0.1 to 0.5 μm and performing the first electroplating step S15, it is shown in FIG. Such as the surface of the convex surface of the resin substrate, which is not dependent on the shape of the projections, and has a lower gloss (rough surface roughness) than the plated surface subjected to the gloss metal plating process described later, and has a fine unevenness. A bright nickel plating film is formed.

  Next, the second electroplating process S17 is performed. In this second electroplating treatment step S17, a bright metal plating is performed on the treated surface after the first electroplating treatment step so that the center line average roughness Ra is in the range of 0.03 μm or less.

  Specifically, compared to the above semi-gloss metal plating treatment, soaking in a copper sulfate bath in which the addition amount of the leveling agent to be added is adjusted so that the electrodeposition is high and the leveling action is high, Electrical copper plating is performed between the electrode and the treated surface on which the semi-gloss metal plating is applied.

  In this way, by performing bright metal plating so that the center line average roughness Ra is in the range of 0.03 μm or less, the plated surface with irregularities as shown in FIG. 2 is leveled, and the surface becomes A smoothed bright copper plating film is formed.

  Finally, an electrochrome plating process S18 is performed. This chrome plating treatment is a generally known chrome plating treatment, which is excellent in surface aesthetics, difficult to discolor in the atmosphere, and is harder and has a smaller friction coefficient than other plating films. A coating can be obtained.

  In the present embodiment, the chrome plating process 18 is performed after the second electroplating process S17. Between these processes, for example, JIS H 8630 “decorative electroplating on plastic” is described. Such semi-bright nickel plating treatment, bright nickel plating treatment, and joule nickel plating treatment may be sequentially performed.

The present invention will be described below based on examples.
Example 1
First, as a resin base material, a resin base material of ABS resin (UMGABS, plating clade) was prepared. And the plating process shown in the following Table 1 was performed. Specifically, first, ozone water treatment was performed under conditions of an ozone concentration of 30 ppm, a treatment temperature of 20 ° C., and an immersion time of 8 minutes.

Then, as a catalyst adsorption treatment step, a catalyst treatment was performed in a solution in which palladium chloride (PdCl ₂ ) and tin chloride (SnCl ₂ ) were dissolved in an aqueous hydrochloric acid solution at a treatment temperature of 30 ° C. and an immersion time of 2 minutes. . Next, as an activation treatment step, activation treatment was performed in an aqueous sulfuric acid solution under conditions of a treatment temperature of 50 ° C. and an immersion time of 2 minutes, Pd—Sn was oxidized and reduced, Sn was dissolved and removed, and Pd metal was deposited. Note that a series of treatments of the catalyst treatment and the activation treatment in the examples correspond to the catalyst adsorption treatment of the present invention.

  Next, as an electroless plating treatment, a Ni-P plating solution containing nickel sulfate hexahydrate and sodium hypophosphite-hydrate (0.2 M) is treated at a temperature of 50 ° C. and an immersion time of 10 minutes. Under conditions, electroless nickel plating was deposited.

Next, as semi-bright nickel plating treatment (first electroplating treatment step), nickel sulfate 200 to 320 g / liter, nickel chloride 50 ± 20 g / liter, boric acid 40 ± 10 g / liter, and additives As described below, the saccharin: sodium naphthalenesulfonate: 1-4 butynediol mass ratio shown in Table 2 as (leveling agent) is 1: 5: 0.1, and the saccharin is 0.1 gram / liter. Electroless nickel is added under the conditions of a treatment temperature of 40 to 70 ° C. (50 ° C.) and a current density of ^{2 to} 10 A / dm ² (3 A / dm ² ) by adding them in a smaller amount than the bright copper plating treatment. Semi-bright nickel plating was deposited on the surface of the plating layer. In addition, the value described in the parenthesis is a numerical value actually implemented, and the range of the numerical value described before indicates a preferable range.

Further, as bright copper plating treatment (second electroplating treatment step), copper sulfate 150 to 250 g / liter (200 g / liter), sulfuric acid 10 to 100 g / liter (50 g / liter), chloride ion 10 100 milligrams / liter (25 milligrams / liter), and 0.1 to 200 milligrams of a compound having a phenazine compound, a safranine compound, a polyalkyleneimine, a thiourea derivative, a polyacrylic acid amide, or a dithiocarbamic acid group as an additive (10 In the condition of 10-50 ° C. (30 ° C.) and current density of 0.1-10 A / dm ² (4 A / dm ² ), the surface of the semi-bright nickel plating layer is bright copper. Plating was deposited. In addition, the value described in the parenthesis is a numerical value actually implemented, and the range of the numerical value described before indicates a preferable range.

Next, a semi-bright nickel plating process was performed. This semi-bright nickel plating treatment is a treatment that improves corrosion resistance by preferentially corroding nickel, which has a higher ionization tendency than copper. Specifically, nickel sulfate hexahydrate 300 gram / liter, nickel chloride hexahydrate 75 gram / liter, and boric acid 45 gram / liter plating solution, treatment temperature 50 ° C., current density 4 A / dm. ^2. Semi-bright nickel plating was deposited on the surface of the bright copper plating layer under the condition of energization time of 15 minutes.

Next, a bright nickel plating treatment was performed. This bright nickel plating treatment is a treatment that further enhances corrosion resistance by preferentially corroding bright nickel having a low natural potential with respect to semi-bright nickel. Specifically, nickel sulfate hexahydrate 300 grams / liter, nickel chloride hexahydrate 75 grams / liter, boric acid 50 grams / liter, and a plating solution containing a brightener containing an appropriate amount of a sulfur compound the treatment temperature is 50 ° C., a current density of 4A / dm ^2, under conditions of energization time 15 minutes, on the surface of the semi-bright nickel plating layer to precipitate a bright nickel plating.

Furthermore, a Joule nickel plating process was performed. This Joule nickel plating process is a process for obtaining a microporous chrome plating layer in a chrome plating process described later. Specifically, nickel sulfate hexahydrate 300 gram / liter, nickel chloride hexahydrate 75 gram / liter, boric acid 50 gram / liter, brightener containing appropriate amount of sulfur compound, and appropriate amount of non-conductive Nickel plating is deposited on the surface of the bright nickel plating layer in a plating solution containing conductive fine particles (kaolin, glass fine particles, etc.) at a treatment temperature of 50 ° C., a current density of 4 A / dm ² , and an energization time of 10 minutes. It was.

Furthermore, chromium plating treatment was performed. This chromium plating treatment is a treatment for improving the appearance of the plating treatment surface, preventing discoloration in the atmosphere, hardening the plating film, and reducing the friction coefficient of the surface. Specifically, the surface of the Joule nickel plating layer was applied to a plating solution of 300 g / liter of chromic anhydride and 3 g / liter of sulfuric acid under the conditions of a treatment temperature of 50 ° C., a current density of 50 A / dm ² , and an energization time of 10 minutes. Then, chromium plating was deposited.

(Evaluation)
Using the stylus type surface shape measuring machine, the surface roughness after the semi-bright nickel plating treatment (first electroplating treatment) and the bright copper plating treatment (second electroplating treatment) was used. The thickness (centerline average roughness Ra) was measured. The results are shown in Table 3. Furthermore, the obtained plating surface was visually observed under room light, and the occurrence frequency of unevenness (roughness degree) was evaluated in five stages. The results are also shown in Table 3. Note that the smaller the number of levels, the greater the number of occurrences.

(Example 2)
By performing the same series of steps as in Example 1, the surface of the resin base material of the ABS resin was plated. The difference from Example 1 is that in the semi-bright nickel plating treatment (first electroplating treatment step), the amount of the added leveling agent is changed to the amount shown in Table 2. The same evaluation as in Example 1 was performed for Comparative Example 1. The results are shown in Table 3.

(Comparative Example 1)
By performing the same series of steps as in Example 1, the surface of the resin base material of the ABS resin was plated. The difference from Example 1 is that the semi-bright nickel plating process (first electroplating process) is not performed. The same evaluation as in Example 1 was performed for Comparative Example 1. The results are shown in Table 3.

(Comparative Examples 2 and 3)
By performing the same series of steps as in Example 1, the surface of the resin base material of the ABS resin was plated. The difference from Example 1 is that in the semi-bright nickel plating treatment (first electroplating treatment step), the amount of the added leveling agent is changed to the amount shown in Table 2. The same evaluation as in Example 1 was performed for Comparative Examples 2 and 3. The results are shown in Table 3.

(Results and discussion)
In Comparative Example 1, since the first electroplating treatment was not performed, the convex shape of the resin base material appeared on the surface of the plating, and as a result, it was considered that the roughness was greater than in Examples 1 and 2. .

  From the relationship between the amount of leveling agent added in Examples 1 and 2 and Comparative Examples 2 and 3 shown in Table 2 and the centerline average roughness Ra of the semi-gloss metal plating, the leveling added in the first electroplating treatment step. As the additive amount increases, the centerline average roughness Ra of the semi-gloss metal plating increases.

  Moreover, the surface roughness of the bright copper plating of Examples 1 and 2 was smaller than that of Comparative Example 2. This is because in the case of Comparative Example 2, the amount of the leveling agent added in the first electroplating treatment step was large, so that the uniform electrodeposition was low, but the unevenness not depending on the protrusions on the surface of the resin substrate It is considered that the center line average roughness Ra of the semi-gloss metal plating is increased. As a result, even if the second electroplating treatment is performed, the treatment surface cannot be sufficiently smoothed, and the remaining unevenness appears on the plating treatment surface, resulting in poor plating gloss.

  Furthermore, in the first electroplating treatment step, since Comparative Example 3 had a lower leveling agent addition amount than Examples 1 and 2, the uniform electrodeposition was increased and the surface of the resin substrate was uneven. It is considered that the part was not smoothed. As a result, even when the second electroplating treatment is performed, the remaining surface protrusions appear in the shape of the plating treatment surface, and it is considered that the roughness is greater than in Examples 1 and 2.

  From the above, as is clear from Examples 1 and 2, semi-gloss metal plating is performed so that the center line average roughness Ra is in the range of 0.1 to 0.5 μm on the treated surface after the electroless plating treatment. In the second electroplating process, the surface can be smoothed, and in the second electroplating process, the centerline average roughness Ra is determined from the experiments and experiences of the inventors. If the gloss metal plating is performed so as to be in the range of 0.03 μm or less (more preferably 0.02 μm or less from this example), a glossy plated surface with no unevenness can be obtained.

The flowchart which showed each process of the plating processing method to the resin base material which concerns on this embodiment. The figure for demonstrating the plating process surface at the time of performing the plating process method by FIG. The figure for demonstrating the plating process surface at the time of performing the conventional plating process method.

Explanation of symbols

  S11: Molding step, S12: Ozone water treatment step, S13: Alkali treatment step, S14: Catalyst adsorption treatment step, S15: Electroless plating treatment step, S16: First electroplating treatment step, S17: Second electroplating Process, S18: Electrochrome plating process

Claims (4)

A step of performing ozone water treatment on the treated surface of the resin substrate having an unsaturated bond;
Performing a catalyst adsorption process for adsorbing a metal catalyst on the treated surface;
A process of performing electroless plating treatment on the treated surface after the catalyst adsorption treatment;
A first electroplating treatment step for performing a semi-gloss metal plating treatment on the treated surface after the electroless plating treatment so that the center line average roughness Ra is in the range of 0.1 to 0.5 μm;
A second electroplating treatment step for performing a bright metal plating treatment on the treated surface after the first electroplating treatment step so that the center line average roughness Ra is in a range of 0.03 μm or less;
A method for plating a resin base material, comprising:   A leveling agent is added to the plating solution for the semi-gloss metal plating treatment and the bright metal plating treatment, and the plating solution for the semi-gloss metal plating treatment is higher than the plating solution for the bright metal plating treatment. The method for plating a resin base material according to claim 1, wherein the amount of addition is small.   The electroless plating process is an electroless nickel plating process, the semi-bright metal plating process is a semi-bright nickel plating process, and the bright metal plating process is a bright copper plating process. Item 3. A resin plating treatment method for a resin substrate according to Item 1 or 2.   4. The method according to claim 1, further comprising a step of performing an alkali treatment by bringing an alkali solution containing at least a surfactant into contact with the treated surface after the ozone water treatment before the catalyst adsorption treatment step. The plating method to the resin base material of description.

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