JP2019030996A - Molding - Google Patents

Abstract

To provide a molding that is able to prevent a surface thereof from exhibiting a rainbow color or looking as if it contains foreign matter, due to thin-film interference, while maintaining rich feeling without marring metal feeling unique to a silver mirror layer.SOLUTION: A molding has a base material. The molding also has an undercoat layer, a silver mirror layer, and a top coat layer stacked on the base material in that order from bottom. A surface roughness Rz on the silver mirror layer side of the undercoat layer or a surface roughness Rz on the top coat layer side of the silver mirror layer is equal to or greater than 2.0.SELECTED DRAWING: None

Description

  The present invention relates to a molded article.

The molded product is often formed of a resin, and surface coating is performed to protect the surface.
Specifically, in automotive molded products, the texture of the exterior surface is also important, so an undercoat layer that flattens on the base material, a silver mirror layer that improves the texture, a top coat layer that protects the surface, A surface coat consisting of three layers is performed.

The silver mirror layer has a metallic luster and can give a deep texture to the molded product. However, the silver mirror layer is covered with a top coat because of its alteration in the air and its susceptibility to damage (for example, patents). Reference 1).
Further, in this specification, the lower layer (base material side) of the silver mirror layer is an undercoat, and the upper layer (opposite side of the base material side) of the silver mirror layer is a top coat. Each coat may be a single layer or multiple layers.

JP 2012-143955 A

However, since the molded article as described above has a multilayer structure, it may show iridescence due to thin film interference.
Thin film interference is a rainbow color caused by the reflected light from each layer interfering with each other. It is well known when there is an oil film in a puddle, the surface of a soap bubble, etc. May appear to be undesirable.
Moreover, in the molded article for automobiles, attention is required for the surface appearance, and it is not preferable that foreign matters appear.

  The present invention provides a molded product capable of suppressing the appearance of rainbow colors due to thin film interference and the appearance of foreign matter on the surface while maintaining a deep texture without impairing the metallic feeling unique to the silver mirror layer. The purpose is to provide.

The present invention relates to the following.
(1) A substrate and an undercoat layer, a silver mirror layer, and a topcoat layer sequentially laminated on the substrate from the bottom, and the surface roughness Rz on the silver mirror layer side of the undercoat layer or the silver mirror A molded product having a surface roughness Rz of 2.0 or more on the topcoat layer side of the layer.
(2) The molded article according to (1), wherein the undercoat layer has a filler, and the average particle diameter of the filler is larger than 2.5 μm.
(3) The molded product according to (1) or (2), wherein the thickness of the undercoat layer is 5 to 25 μm.

  According to the present invention, it is possible to suppress the appearance of a rainbow color due to thin film interference on the surface and the appearance of foreign matters while maintaining a deep texture without damaging the unique metallic feeling of the silver mirror layer. it can.

<Base material>
The base material described in the present specification is for laminating an undercoat layer to be described later, and the material is not particularly limited, but a metal molded product or a synthetic resin molded product can be used. As the resin, a thermosetting resin or a thermoplastic resin can be used.
As the thermoplastic resin, polyethylene, polypropylene, polystyrene, polycarbonate, acrylic, polyvinyl chloride, vinyl polymer, polyester, polyamide, ABS resin, polyester resin, thermoplastic elastomer, and the like can be used.
As the thermosetting resin, silicon resin, polyurethane resin, polyester resin, melanin resin, epoxy resin, phenol resin, urea resin, or the like can be used.
Specifically, there are polypropylene, polycarbonate, and ABS resin as long as they are used for automobile molded products. Polypropylene has a small specific gravity among resins, is easy to process, has high tensile strength, impact strength, and compressive strength, and is excellent in weather resistance and heat resistance. ABS resin is a resin that is relatively easy to apply after surface treatment among plastic materials, and that can be easily applied after molding, etc., has excellent chemical resistance and rigidity, impact resistance, heat resistance, and cold resistance. Also excellent. Polycarbonate has high impact resistance among plastic materials, is excellent in weather resistance and heat resistance, is excellent in transparency, is easy to process, and is relatively light and durable among plastic materials.

<Undercoat layer>
The undercoat layer described in this specification is arranged on the above-described base material, and forms a smooth surface before placing a silver mirror layer to be described later, and the substrate and the silver mirror layer. It is preferable to use a material having excellent adhesion.
Specifically, there are fluorine resin paint, polyester resin paint, epoxy resin paint, melanin resin paint, silicone resin paint, acrylic silicone resin paint, acrylic urethane resin paint, etc., but acrylic silicone resin paint, acrylic resin are particularly preferable. It is a urethane resin paint.
Acrylic silicone resin paint has high adhesion to the base, high gloss retention and color retention, and excellent chemical resistance, oil resistance and water resistance.
The acrylic urethane resin paint has a soft coating film, excellent adhesion, and excellent durability, weather resistance, and chemical resistance.
The thickness of the undercoat layer is not particularly limited, but is preferably about 5 to 25 μm because a smooth surface is easily secured.
It is preferable to add a filler for increasing the surface roughness to the undercoat layer. As such a filler, for example, resin fine powder can be used. Moreover, the average particle diameter is preferably more than 2.5 μm, more preferably 5 μm or more, and even more preferably 10 μm or more. The average particle diameter can be measured as a weight average particle diameter by a laser diffraction scattering method such as a particle size distribution measuring apparatus manufactured by Beckman Coulter.
In addition, a primer layer may be interposed in order to enhance the adhesion between the undercoat layer and the substrate depending on the material of the substrate.

<Silver mirror layer>
The silver mirror layer described in the present specification means a silver thin film layer, a vapor deposition method in which metallic silver is attached by sublimation, a sputtering method using a vacuum vessel, a transfer method in which a silver thin film is formed on a film in advance and transferred, It can be formed by a plating method or the like.
The thickness of the silver mirror layer is not particularly limited, but is preferably about 50 to 200 nm. When the thickness is 50 nm or more, the transparency is low and the role of a silver mirror is easily achieved, and when the thickness is 200 nm or less, silver discoloration is small.

<Topcoat layer>
The top coat layer described in the present specification protects the silver mirror layer described above, and uses a clear or transparent colored paint that does not hide the silver mirror layer or a colored color clear resin coating. Specifically, a thermosetting resin can be used.
As specific thermosetting resins, fluorine resin paint, polyester resin paint, epoxy resin paint, melanin resin paint, silicon resin paint, acrylic silicon resin paint, acrylic urethane resin paint, etc. can be used. Acrylic silicon resin paint It is particularly preferable to use an acrylic urethane paint.
Acrylic silicone resin paint has high adhesion to the base, high gloss retention and color retention, and excellent chemical resistance, oil resistance and water resistance.
The acrylic urethane resin paint has a soft coating film, excellent adhesion, and excellent durability, weather resistance, and chemical resistance.
The top coat layer is not necessarily a single layer, and may be a plurality of layers.
When the top coat layer is a plurality of layers, the depth of the top coat is increased and a glossy texture is easily produced.
Although the thickness of a topcoat layer is not specifically limited, About 20-40 micrometers is preferable.
When the thickness is 20 μm or more, the above-described silver mirror layer can be sufficiently protected, and when it is 40 μm or less, cracks, peeling, poor adhesion, and the like due to secular change are difficult to occur.
Moreover, although it has a metallic luster by having a silver mirror layer as a base, since the top coat of the outermost layer is a resin cured product, its thermal conductivity is lower than that of metal, and there is no feeling as a touch.

<Surface roughness Rz>
The surface roughness Rz described in this specification is defined by “JIS-B0601-2013”, and is the sum of the highest mountain height and the deepest valley depth.

  Examples of the present invention will be described below, but the present invention is not limited to the following examples.

(Formation of undercoat layer)
As shown in Table 1 to be described later, the undercoat layer was formed by changing each of Examples 1 to 3 and Comparative Examples 1 and 2.

Example 1
Prepare a flat ABS substrate of length: 70 mm x width: 150 mm x thickness: 3 mm, and degrease and clean the surface of this substrate with a waste cloth containing IPA (isopropyl alcohol) to remove oil film, dirt and dust. Removed.
The removed substrate is dried, and MSPS undercoat clear D (“MSPS”) is an abbreviation of “Mitsubishi Paper Silver Plating System (trade name, manufactured by Mitsubishi Paper Industries Co., Ltd.)” manufactured by Ohashi Chemical Industry Co., Ltd. ) And MSPS undercoat thinner No. 15: MSPS undercoat additive L and MSPS undercoat curing agent N: 25: 35: 0.5: 4 (ratio in parts by mass: UC) and filler a (Sekisui Plastics Co., Ltd.) Company, product name: MBX-5, average particle size: 5 μm) is mixed with 0.2 parts by mass, stirred, spray gun sprayed, dried in a drying furnace set at 80 ° C. for 1 hour and average film thickness of 15 μm. An undercoat layer was formed.

(Example 2)
It was formed in the same manner as in Example 1 except that the filler was changed to the filler b (manufactured by Sekisui Plastics Co., Ltd., trade name: MBX-12, average particle diameter: 12 μm).

(Example 3)
Prepare an ABS base material having a length of 70 mm × width: 150 mm × thickness: 3 mm (texture texture 25 μm), and the surface of this base material is degreased and washed with a waste cloth containing IPA (isopropyl alcohol). Oil film, dirt and dust were removed.
The removed substrate was dried, and the formulation: UC was stirred and formed in the same manner as in Example 1.

(Comparative Example 1)
It was formed in the same manner as in Example 1 except that the blending of the filler a in Example 1 was omitted.

(Comparative Example 2)
It was formed in the same manner as in Example 1 except that the filler was changed to the filler c (manufactured by Sekisui Plastics Co., Ltd., trade name: MBX-2H average particle size 2.5 μm).

(Formation of silver mirror layer)
After spray-cleaning the substrate on which the undercoat layer has been formed with pure water, a treatment liquid MSPS-Sa1A (trade name) for silver mirror plating manufactured by Mitsubishi Paper Industries Co., Ltd. is spray-coated, and after sufficient spray cleaning with pure water After applying MSPS-Sa2A (trade name), a silver mirror plating treatment solution manufactured by Mitsubishi Paper Industries, Ltd., and applying silver mirror deposition activation treatment, with a two-head spray gun, for silver mirror plating made by Mitsubishi Paper Industries Co., Ltd. Two liquids of treatment liquid MSPS-Ag (trade name) and silver mirror plating treatment liquid MSPS-Do (trade name) are applied at the same time to form a silver mirror layer by silver mirror reaction, and then spray-washed with pure water. A silver mirror plating treatment solution MSPS-R1A (trade name) manufactured by the company was applied, and further spray cleaning with pure water was performed. Next, in order to remove the water | moisture content of a silver mirror layer, after blowing compressed air (air blow), it was dried for 30 minutes in the drying furnace set to 45 degreeC.

(Formation of top coat layer)
After confirming that the temperature of the molded product after drying the silver mirror layer was room temperature (25 ° C.), the top coat layer was MSPS top coat clear M manufactured by Ohashi Chemical Industry Co., Ltd., and MSPS top coat thinner. P-7, MSPS topcoat curing agent W, and MSPS colorant black were mixed at a ratio of 20: 20: 5: 0.4 (parts by mass), stirred, and sprayed with a spray gun. In a drying oven set at 80 ° C., drying was performed for 45 minutes to form a topcoat layer having an average film thickness of 25 μm.

(Appearance thin film interference fringe evaluation)
The molded products of Examples and Comparative Examples were visually observed by 50 test subjects to confirm whether thin film interference fringes (rainbow colors) were generated.
Evaluation is based on the number of people who have determined that no rainbow has occurred. If it is judged that 40 or more people are not present, “◎”, if it is judged that 30 to 39 people are absent, “○”, and 20 to 29 or less people are judged to be none. In this case, “△” was given, and if it was judged that 19 or less were none, “x” was given.

(Appearance of foreign matter)
About the molded article of an Example and a comparative example, visual observation was performed by 50 test subjects, and the presence or absence of the appearance foreign material was confirmed.
The evaluation is based on the number of people who are judged to be free of foreign matter. If it is judged that there are no more than 40 people, “◎”, if it is judged that 30 to 39 people are none, “○”, and 20 to 29 people or less are judged as none. “△”, and “x” if 19 or less were judged to be absent.

(Appearance brightness evaluation)
The molded products of Examples and Comparative Examples were visually observed by 50 test subjects to confirm the presence or absence of appearance luminance.
The evaluation is based on the number of people judged to have a sense of brightness. If it is judged that there are 40 or more people, “◎”, if it is judged that there are 30 to 39 people, “○”, and 20 to 29 people or less are judged. “△”, and “x” if it was judged that there were 19 or less.

(Appearance metal texture evaluation)
About the molded article of an Example and a comparative example, visual observation was performed by 50 test subjects, and the presence or absence of the external appearance metal texture was confirmed.
The evaluation is based on the number of people who judged that there is a metal texture. If it is judged that there are 40 or more people, “◎”, if it is judged that there are 30 to 39 people, “○”, and 20 to 29 people or less are judged. “△”, and “x” if it was judged that there were 19 or less.

(Hand / Hook evaluation)
About the molded product of an Example and a comparative example, 50 test subjects performed palpation and confirmed the presence or absence of touch and a catch.
The evaluation was performed by the number of persons who asked the subjects to wear cotton gloves, and stroked the surface of the molded product with the worn cotton gloves and judged that there was no catch. When it was judged that there was no name, “◯” was given, and when it was judged that 20 to 29 or less were none, “Δ”, and when 19 or less were judged to be none, “X” was given.

(Surface roughness measurement)
About the molded article of an Example and a comparative example, after formation of an undercoat layer, according to the procedure prescribed | regulated to "JIS-B-0633-2001" on the surface of an undercoat layer, a roughness meter measurement test is performed, Rz (JIS) -B-0601-2013) was calculated. The surface roughness of the undercoat layer surface corresponds to the surface roughness of the undercoat layer on the silver mirror layer side. Since the silver mirror layer is a nano-level thin film, the surface roughness of the silver mirror layer corresponds to the surface roughness of the undercoat layer. The surface roughness of the silver mirror layer corresponds to the surface roughness of the silver mirror layer on the topcoat layer side.
The roughness meter measurement is a stylus type, and the tip of the stylus is placed on the surface to be measured, the stylus is moved along the surface to be measured, and the amount of vertical movement due to surface irregularities is electrically expanded. Is a method of measuring.

  The evaluation results are shown in Table 1 below.

From the results shown in Table 1, in Comparative Examples 1 and 2 where the surface roughness Rz of the undercoat layer is smaller than 2.0, there is a feeling of brightness, a metal texture, there is no catch, and there is no appearance defect due to foreign matter mixing, An appearance defect of the interference fringe rainbow was confirmed.
On the other hand, in Examples 1 to 3 in which the surface roughness Rz of the undercoat layer is 2.0 or more, the brightness and the metal texture are not impaired, and there is no catch, and the appearance due to interference fringes of rainbows and foreign matters is mixed. It was confirmed that there was no defect.

Claims (3)

  A base material, and an undercoat layer, a silver mirror layer, and a top coat layer sequentially laminated on the base material from the bottom, and the surface roughness Rz on the silver mirror layer side of the undercoat layer or the silver mirror layer A molded product having a surface roughness Rz of 2.0 or more on the topcoat layer side.   The molded article according to claim 1, wherein the undercoat layer has a filler, and an average particle diameter of the filler is larger than 2.5 μm.   The molded article according to claim 1 or 2, wherein the thickness of the undercoat layer is 5 to 25 µm.