JP2002293967A - Method for producing urethane resin plated product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a urethane resin cast material having a plated film excellent appearance and adhesion. SOLUTION: This method for producing a urethane resin plated product comprises a coating step I of coating the surface of the urethane resin cast material with a urethane coating, a coating step II of coating the top surface of the film I obtained by the coating step I with an ABS resin coating, an electroless plating step of carrying out plating by the electroless plating using a desired metal on the film II prepared by the coating step II and an electrolating step of further performing the plating by electroplating using a desired metal on the plated film prepared by the electroless plating step. The ABS resin coating is a composition comprising 30-35 pts.wt. of an ABS resin, 55-45 pts.wt. of cyclohexanone and 15-20 pts.wt. of toluene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a urethane resin-plated product used for, for example, automobile parts.

[0002]

2. Description of the Related Art Casting articles using urethane resin are often used for various automobile parts. Some components, such as rims and radiator grills, are required to be plated to give a metal-like appearance. Conventionally, as a plated resin molded product having a metal-like appearance, ABS
(Acrylonitrile-butadiene-styrene) resin-plated products are known. Plating for ABS resin (Cu-
Ni-Cr) processing steps are generally 1) degreasing, 2) etching, 3) neutralization, 4) catalyzing (catalyst),
5) Accelerating, 6) Electroless nickel plating,
7) activation, 8) copper sulfate plating, 9) nickel plating,
10) A process such as chrome plating is included (water washing is performed between each step). Until now, there has been no established specific method for plating a urethane resin casting, and therefore, after coating (surface treatment) a urethane-based paint on the surface as a primer coating, a normal A
It has been carried out in the same manner as described above by flowing to a BS resin plating line.

[0003]

However, in the urethane resin-plated product obtained as described above, the interface between the electroless nickel plating film of the above 6) and the cast product (urethane-based paint surface-treated surface). There was a problem that defects such as blistering, floating, and peeling occurred, and the yield was poor. Actually, the adhesion of the plating film obtained was weak (0.3 kg / cm ² ) such that the plating film was peeled off in a cross-cut cellotape (registered trademark) peeling test. The present invention has been made in view of the above, and an object of the present invention is to provide a method for producing a urethane resin-plated product having good appearance and excellent adhesion.

[0004]

Means for Solving the Problems To achieve the above object, the present inventor studied to apply an ABS resin paint to a urethane resin cast product and then perform plating thereon.
Desirable results were not obtained in terms of the appearance and the adhesion between the ABS resin layer and the cast product. Therefore, it has been found that a desired appearance and adhesion can be obtained by combining the primer coating and the ABS resin coating as a base treatment and further improving the composition of the ABS resin coating, and have completed the present invention. .

That is, the method for producing a urethane resin-plated product according to the present invention comprises a coating step I in which a surface of a urethane resin casting is coated with a urethane-based paint, and a coating film I obtained in the coating step I described above. A coating step II for applying an ABS resin coating, and a coating film II obtained in the coating step II
An electroless plating step of performing plating by electroless plating using a desired metal on the above, and an electrolytic plating step of performing plating by electroplating further using a desired metal on the plating film obtained by the electroless plating step. And the ABS resin paint is a composition comprising: ABS resin: 30 to 35 parts by weight Cyclohexanone: 55 to 45 parts by weight Toluene: 15 to 20 parts by weight

Further, another method for producing a urethane resin-plated product according to the present invention comprises a coating step I of coating a surface of a urethane resin casting with a urethane-based coating, and a coating film I obtained in the coating step I. A coating step II of coating an ABS resin coating thereon, and a coating film II obtained by the coating step II
An electroless plating step of performing plating by electroless plating using a desired metal on the above, and an electrolytic plating step of performing plating by electroplating further using a desired metal on the plating film obtained by the electroless plating step. And the ABS resin paint is a composition comprising: ABS resin: 30 to 35 parts by weight Cyclohexanone: 15 to 35 parts by weight Toluene: 15 to 20 parts by weight Methyl ethyl ketone: 40 to 10 parts by weight It is assumed that.

As described above, in the method for producing a urethane resin-plated product of the present invention, a primer coating and an ABS resin coating are combined as a base treatment, and the ABS resin coating has a composition using a predetermined solvent in a predetermined ratio. The primer layer is made of a material (urethane resin casting) and A
The adhesion with the BS resin layer is enhanced, and the ABS resin layer enhances the adhesion between the primer layer (material) and the plating film layer. As a result, a good plating film that is smooth and has excellent adhesion can be obtained. .

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. The method for producing a urethane resin plated product of the present invention comprises at least the following steps: A. coating step I in which a urethane-based paint is applied to the surface of the urethane resin casting; B. a coating step II of coating an ABS resin paint on the coating film I obtained in the coating step I; An electroless plating step of plating the coating film II obtained in the coating step II by electroless plating using a desired metal; An electroplating step of performing plating by electroplating using a desired metal on the plating film obtained by the electroless plating step. FIG. 1 is a cross-sectional view showing an example of a urethane resin-plated product obtained by the production method of the present invention. As shown in the figure, a urethane resin coating film (1) is coated on a urethane resin casting (1). (2), A
BS resin coating film II (3), electroless plating film (4), electrolytic plating film such as Cu plating film (5), Ni plating film (6), Cr plating film (7)
Are laminated in this order to obtain a urethane resin plated product (10).

In the present invention, the cast product (1) is, for example, a urethane resin cast product for a prototype used for an automobile part or the like. If it is a cast product such as a prototype,
A master model (a wooden mold, etc.) of a desired cast product is manufactured, and a silicon resin mold for a prototype is manufactured using the obtained master model (the master model is suspended in a container, and the silicone resin is poured there). After injecting and curing, divide into two and take out the master model), and inject the urethane resin into the obtained prototype silicone resin mold (inject the urethane resin with the silicone resin mold held together) and cure it. A desired type of urethane resin casting is completed.

[0010] The urethane resin is a two-part cast type, in which a polyol is pre-reacted with a substantial excess of diisocyanate to form a liquid prepolymer, which is then cured with a curing agent (diol, amine, water). ) And cured at room temperature. The starting materials and the degree of polymerization (molecular weight) can be arbitrarily selected according to the intended use. In addition, urethane resin is a primer paint or A
Depending on the baking / drying temperature of the BS paint, it is necessary to select one having heat resistance higher than that temperature. Further, it is preferable to increase the crosslink density as necessary so that the surface is not deteriorated by the solvent attack by the solvent used for the paint.

The coating step I of the step A is a so-called surfacer treatment. Cast products have lower surface accuracy than injection-molded products, so if the surface is polished as it is, the cast product may become thinner, so prevent this and fill in minute irregularities. Therefore, the surface of the cast product is painted. The urethane-based paint is selected as the treatment agent because it has good adhesion to both the urethane resin cast product and the ABS resin coating film to be subsequently laminated, and is also preferable in terms of improving leveling properties. is there. The type of urethane-based paint is not particularly limited,
It may be a two-pack type or a one-pack type. For example, a two-pack type “Alex 85 C-2” (Nippon Kako Paint Co., Ltd.) or the like can be preferably used.

The urethane-based paint is applied by, for example, air spray coating, and thereafter, is baked, dried, and cured to form the coating film I (2). If the baking temperature is too low, the solvent may remain in the coating film and cause cracks. Therefore, it is preferable to set a necessary baking temperature according to the boiling point of the solvent. For example, in the case of the above-mentioned "Alex 85 C-2", it contains an acrylic polyol resin as a main component, a polyisocyanate as a curing agent, and a thinner as a solvent. Is preferred. The dry film thickness of the coating film I (2) is preferably about 10 to 55 μm, and more preferably about 20 to 25 μm, for example.

Next, in the above step B, an ABS resin paint is applied on the urethane-based paint film I (2).
A resin coating film II (3) is formed. This painting process I
The ABS resin paint used in I is a composition comprising: ABS resin: 30 to 35 parts by weight cyclohexanone: 55 to 45 parts by weight Toluene: 15 to 20 parts by weight, or ABS resin: 30 to 35 parts by weight cyclohexanone : 15 to 35 parts by weight Toluene: 15 to 20 parts by weight Methyl ethyl ketone: 40 to 10 parts by weight.

The ABS resin coating is applied by, for example, air spray coating, and thereafter, is baked, dried and cured to form the coating film II (3). If the baking temperature is too low, the solvent may remain in the coating film and cause cracks. Therefore, in the ABS resin coating composition combining the above high boiling point solvent and low boiling point solvent, about 8%
It is preferable to carry out at a temperature of 0 ° C. or higher for about 60 to 120 minutes (the lower the temperature, the longer the time). The dry film thickness of the coating film II (3) is preferably about 5 to 25 μm, and the coating and baking are repeated a plurality of times (2 to 3) until a desired film thickness is obtained.
It is preferable to carry out the process.

The above-mentioned coating composition (urethane-based coating, ABS resin coating) used in the present invention may contain various additives (antioxidant, plasticizer, etc.) as necessary within a range not to impair the object of the present invention. , A lubricant, etc.). Each component can be mixed by a commonly used method such as a roll, a Banbury mixer, and a kneader.

After the undercoating treatment comprising the above steps A and B, the coating film II obtained in the coating step II is obtained.
(3) An electroless plating film (4) is formed thereon by electroless plating using a desired metal. In the electroless plating step C, the following pretreatments usually performed: mounting of a plating jig, degreasing, etching, neutralization, catalyzing (catalyst), and accelerating (including water washing between each plating step) )) Are included as needed. Nickel can be preferably used as the electroless plating metal.

Next, electrolytic plating using a desired metal is further performed on the electroless plating film (4) obtained in the above electroless plating step. In this electrolytic plating step D, Cu-Ni-Cr plating is preferably performed,
It is not limited to this. Specifically, it is preferable that activation is performed after washing the electroless plating film (4) with water, followed by copper sulfate plating, semi-bright nickel plating, bright nickel plating, and chromium plating in this order ( Water washing is included between each step), whereby a Cu plating film (5), a Ni plating film (6), and a Cr plating film (7) are sequentially laminated as electrolytic plating films.

Each of the above processes is performed according to a usual method. An example of the preferable processing solution and the processing conditions is shown below. Degreasing: [sodium sulfate 20 g / L (liter), sodium phosphate 20 g / L, surfactant 2 g / L] 40 to 60 ° C.
3-5 minutes Etching: [Sodium sulfate 20g / L, sodium phosphate 2
0 g / L], 65-70 ° C, 8-15 minutes Neutralization: [concentrated hydrochloric acid 50 ml] room temperature, 0.5-2 minutes Catalyzing: [palladium chloride 0.2 g / L, stannous chloride 5-20 g / L, concentrated hydrochloric acid 100-200m
l] Room temperature, 3 to 5 minutes Accelerating: [Sulfuric acid 80 to 150 g / L] 30
-50 ° C, 3-6 minutes Electroless nickel plating: [nickel sulfate 20 g / L, sodium hypophosphite 20 g / L, ammonium citrate 50
g / L] pH 8 to 9.5, 30 to 40 ° C, 5 to 10 minutes Activation: [sulfuric acid 80 to 150 g / L] room temperature, 0.5 to 1
Min Copper sulfate plating: [Copper sulfate 200 g / L, sulfuric acid 50 g /
L, a brightening agent, an appropriate amount] Dk2~4A ^/ dm 2, 20~30
℃, 20-60 minutes Semi-bright nickel plating: [280 g / L nickel sulfate,
Nickel 40 g / L chloride, boric acid 40 g / L, semi-gloss agent, an appropriate ^{amount] Dk3A / dm 2, 45~55 ℃} , 10~30
Min bright nickel plating: nickel sulfate 280 g / L, nickel chloride 40 g / L, boric acid 40 g / L, brighteners, ^{qs] Dk2~4A / dm 2, 45~55 ℃} , 10~30
Chromium plating: [Chromic acid 250 g / L, sulfuric acid 2.5 g
/ L, trivalent chromium 1-3 g / L] Dk 18-20 A / d
m ² , 45 to 55 ° C., 1 to 3 minutes In the urethane resin plated product obtained by the production method of the present invention, the peeling adhesion strength test is 1.0 to 2.
A high plating film adhesion of 5 kg / cm ² is obtained, and the leveling property is also good.

[0019]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the scope of the present invention. Less than,
Parts by weight are described as parts.

Example 1 A plate-like urethane resin cast product sample (110 mm long × 150 mm wide × 100 mm high) was used as a plating test piece, and the following treatments were sequentially applied to the sample.
Test specimens of urethane resin plated products were prepared.

Primer treatment (coating step I): Using a two-part urethane paint (100 parts of acrylic polyol, 15 parts of polyisocyanate, 70 parts of Alex 85 thinner), after air spray coating, baking and drying at 130 ° C./60 minutes Thus, a coating film I having a dry film thickness of 20 to 25 μm was formed on the cast product. Application of ABS resin paint (coating process II): Top Magic Coat (Okuno Pharmaceutical Co., Ltd .; ABS resin 100)
Parts, cyclohexanone 50 parts, toluene 50 parts)
100 parts and 50 parts of cyclohexanone were mixed to prepare an ABS resin coating composition having the composition shown in Table 1. The resulting ABS resin coating composition was air-sprayed onto the coating film I, baked and dried at 100 ° C./60 minutes to obtain a coating film having a dry film thickness of about 5 μm. Next, after painting similarly
Baking was performed at 00 ° C. for 90 minutes, and a coating film II having a dry film thickness of about 10 μm was formed by two coats and two bake steps.

The electroless plating step and the electrolytic plating step were performed in the following order under the following conditions to obtain urethane resin plated test pieces. Degreasing: [Sodium sulfate 20g / L, sodium phosphate 20g /
L, surfactant 2 g / L] 50 ° C., 4 minutes Etching: [sodium sulfate 20 g / L, sodium phosphate 2
0g / L], 65-70 ° C, 10 minutes Neutralization: [concentrated hydrochloric acid 50ml] room temperature (25 ° C), 1 minute Catalyzing: [palladium chloride 0.2g / L, stannous chloride 15g / L, concentrated hydrochloric acid 150 ml / L] room temperature (25 ° C.), 3 minutes Accelerating: [sulfuric acid 120 g / L] 40 ° C., 5
Min electroless nickel plating: [nickel sulfate 20 g / L, sodium hypophosphite 20 g / L, ammonium citrate 50
g / L] pH 9.0, 35 ° C., 8 minutes Activation: [sulfuric acid 120 g / L] room temperature for 1 minute Copper sulfate plating: [copper sulfate 200 g / L, sulfuric acid 50 g /
L, brightener / appropriate amount] Dk3A / dm ² , 25 ° C., 40 minutes semi-bright nickel plating: [nickel sulfate 280 g / L,
Nickel chloride 40 g / L, boric acid 40 g / L, semi-brightening agent, appropriate amount] Dk3A / dm ² , 50 ° C., 20 minutes Bright nickel plating: [nickel sulfate 280 g / L, nickel chloride 40 g / L, boric acid 40 g / L , Brightener, appropriate amount] Dk3A / dm ² , 50 ° C, 20 minutes Chromium plating: [chromic acid 250g / L, sulfuric acid 2.5g
/ L, trivalent chromium 2 g / L] Dk 18-20 A / d
m ² , 50 ° C., 20 minutes

Example 2 As an ABS resin paint, 100 parts of Top Magic Coat, 25 parts of cyclohexanone and 25 parts of methyl ethyl ketone were mixed to obtain an A composition having the composition shown in Table 1.
A BS resin coating composition was prepared and baked and dried under conditions 8
A urethane resin plated test piece was prepared in the same manner as in Example 1 except that two coats and two baking were performed at 0 ° C./120 minutes and 80 ° C./120 minutes.

Example 3 As an ABS resin paint, 100 parts of Top Magic Coat and 50 parts of methyl ethyl ketone were mixed to prepare an ABS resin paint composition having the composition shown in Table 1, which was baked and dried at 90 ° C. / 60 min, 90 ° C / 6
A urethane resin-plated test piece was prepared in the same manner as in Example 1 except that three coats and three baking were performed at 90 ° C./90 minutes for 0 minute (dry film thickness: about 15 μm).

Comparative Example 1 The same procedure as in Example 1 was carried out except that 100 parts of Top Magic Coat and 50 parts of toluene were mixed as the ABS resin paint and the ABS resin paint composition shown in Table 1 was used. A urethane resin plated test piece was prepared in the same manner as described above.

[Comparative Example 2] As an ABS resin paint, 100 parts of Top Magic Coat, 25 parts of toluene, and 25 parts of methyl ethyl ketone were mixed, and an ABS resin paint composition having the composition shown in Table 1 was used. A urethane resin plated test piece was prepared in the same manner as in Example 1 above.

Comparative Example 3 The same procedure as in Example 1 was carried out except that 100 parts of Top Magic Coat and 50 parts of xylene were used as the ABS resin paint and the ABS resin paint composition shown in Table 1 was used. A urethane resin plated test piece was prepared in the same manner as described above.

Comparative Example 4 As an ABS resin paint, 100 parts of Top Magic Coat, 25 parts of toluene and 25 parts of xylene were used.
Parts, and using the ABS resin coating composition having the composition shown in Table 1 in the same manner as in Example 1 above.
A urethane resin plated test piece was prepared.

The obtained plating test piece was subjected to JIS H
A peeling adhesion strength test (test number 5) was carried out based on -8630 to determine a peeling strength (kg / cm ² ). The appearance of the plating was visually evaluated according to the following criteria. ：: No peeling / flowering phenomenon / cracks on the whole and good leveling property. ２〜: 2-3 cracks occurred. ×: Peeling phenomenon / flowering phenomenon occurred at the edge. Table 1 also shows the results.

[0030]

[Table 1]

From Table 1, it is clear that the plating obtained in the examples of the present invention is superior in both appearance and adhesion in comparison with the comparative examples. In the ABS resin coating of the example, since the content of cyclohexanone or cyclohexanone and methyl ethyl ketone is high, the adhesion of the ABS resin coating to the primer layer (urethane coating) as a base material is improved, and the peeling strength is good. It has become.

[0032]

According to the method for producing a urethane resin-plated product of the present invention, the appearance is improved and the urethane resin-plated product is produced in an amount of 1.0 to 2.5 kg /
Plating with a high adhesion of ² cm ² can be applied to the surface of the urethane resin cast product, and can be effectively used as a method for manufacturing various urethane resin plated products such as automobile parts.

[Brief description of the drawings]

FIG. 1 is a schematic view schematically showing a cross section of a urethane resin-plated product obtained by a production method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 1 Urethane resin casting 2 Urethane coating I 3 ABS resin coating II 10 Urethane plating

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C25D 5/56 C25D 5/56 A // B32B 27/30 B32B 27/30 B 27/40 27 / 40F Terms (reference) 4D075 AE03 BB87Z CA13 CA48 DA06 DA23 DB50 DC13 EA07 EA41 EB12 EB14 EB22 EB38 EC30 4F006 AA37 AB16 AB37 AB52 BA01 DA04 EA01 4F100 AB16 AK51A AK51B AK74C BA04 BA07 BA10ABA10AA18A01B01A03A BB20 DA06 GA01 GA02

Claims (2)

[Claims] 1. A method for producing a urethane resin plated product obtained by resin plating of a urethane resin cast product,
A coating step I for coating a urethane-based coating on the surface of the urethane resin casting, a coating step II for coating an ABS resin coating on the coating film I obtained in the coating step I, and a coating step II obtained in the coating step II. An electroless plating step of performing plating by electroless plating using a desired metal on the coated film II, and plating by electroplating using a desired metal on the plating film obtained by the electroless plating step. Wherein the ABS resin coating is a composition comprising: ABS resin: 30 to 35 parts by weight, cyclohexanone: 55 to 45 parts by weight, toluene: 15 to 20 parts by weight. Manufacturing method of urethane resin plated products. 2. A method for producing a urethane resin plated product obtained by resin plating of a urethane resin cast product,
A coating step I for coating a urethane-based coating on the surface of the urethane resin casting, a coating step II for coating an ABS resin coating on the coating film I obtained in the coating step I, and a coating step II obtained in the coating step II. An electroless plating step of performing plating by electroless plating using a desired metal on the coated film II, and plating by electroplating using a desired metal on the plating film obtained by the electroless plating step. Wherein the ABS resin coating comprises: ABS resin: 30 to 35 parts by weight Cyclohexanone: 15 to 35 parts by weight Toluene: 15 to 20 parts by weight Methyl ethyl ketone: 40 to 10 parts by weight A method for producing a urethane resin-plated product, characterized in that: