Resin product

Abstract

To provide a resin product in which, even when a deep and large local concavity originating from foreign matter exists on a surface of a substrate molded from a resin containing the foreign matter, a concavity generated in a coating film due to reflection of the local concavity is made less noticeable and difficult to recognize with the naked eye, thereby preventing poor appearance.SOLUTION: A resin product includes: a substrate molded from a resin; and a coating film covering a surface of the substrate, wherein the coating film has an arithmetical mean height Sa of 0.2 μm or more, a skewness Ssk of -1.3 or more, and a maximum valley depth Sv is 5 to 30 times the arithmetical mean height Sa.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a resin product including a base material formed of resin and a film coated on the surface of the base material.

Background Art

[0002] Foreign substances may be mixed into resin. In particular, recycled resin obtained by recycling used resin contains many foreign substances such as resin and metal that cannot be removed during the sorting process. Although it is possible to enhance the sorting of foreign substances to increase the purity, there is a limit because the cost and energy increase.

[0003] On the surface of a base material formed of resin containing foreign substances, deep and large local recesses starting from the foreign substances are likely to occur, and since the local recesses are easily recognizable by the naked eye, they cause appearance defects such as rough skin (see Fig. 1). Therefore, it is necessary to coat the surface of the base material with a coating film or the like to make the local recesses difficult to recognize by the naked eye.

[0004] Patent Document 1 discloses that by using a mold having minute irregularities rather than a mirror-finished mold, blow molding is performed at a predetermined temperature, and a coating film having a predetermined film thickness corresponding to the surface roughness of the minute irregularities is applied, it has been found that spots and the like due to rough skin of a parison can be suppressed. Thus, a coating film having a film thickness of 120 μm or less is applied to the outer surface of a molded article blow-molded with a predetermined resin, the surface roughness of the molded article is 3 to 13.5 μm, and an automotive exterior panel having a relationship of T≧4.5H + 10 between the surface roughness (H) of the molded article and the film thickness (T) of the coating film is disclosed. That is, when H is 3 μm, T is made 23.5 μm or more, and when H is 13.5 μm, T is made 70.75 μm or more.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, according to the study by the present inventors, when a coating film with the film thickness described in Patent Document 1 is simply applied to the surface of a substrate on which local recesses (not mentioned in Patent Document 1) are generated as shown in FIG. 1, the recesses generated in the coating film due to the reflection of the local recesses may still be easily recognizable by the naked eye (see the left and center of FIG. 2(a)). For example, when the surface roughness of a predetermined area including local recesses of the substrate is 3 μm, even if it is coated with a coating film having a film thickness of about 50 μm rather than 23.5 μm, recesses that are easily recognizable by the naked eye are generated in the coating film, and a good appearance may not be obtained.

[0007] Therefore, an object of the present invention is to provide a resin product that, even when there are deep and large local recesses starting from foreign substances on the surface of a substrate molded with a resin containing foreign substances, makes the recesses generated in the film due to the reflection of the local recesses inconspicuous and difficult to recognize by the naked eye, and does not result in a defective appearance.

Means for Solving the Problems

[0008] [1] A resin product including a substrate molded with a resin and a film coated on the surface of the substrate, wherein the film has an arithmetic mean height Sa of 0.2 μm or more, a skewness (degree of bias) Ssk of -1.3 or more, and a maximum valley depth Sv of 5 to 30 times the arithmetic mean height Sa. Here, Sa and Ssk are measured in an area of 258 μm × 258 μm that does not include recesses with a valley depth of 5 times or more of Sa. The maximum valley depth Sv is measured in an area of 646 × 646 μm that includes recesses with a valley depth of 5 times or more of Sa.

[0009] [2] The resin product according to [1], wherein the arithmetic mean height Sa is 0.4 μm or more and the skewness Ssk is -0.21 or more.

[0010] [3] The resin product according to [1] or [2], wherein the 85° gloss value of the film is 90 or less.

[0011] [4] The resin product according to [1] or [2], wherein the 85° gloss value of the film is 70 or less.

[0012] [5] The resin product according to any one of [1] to [4], wherein the resin is a recycled resin.

[0013] [6] The resin product according to any one of [1] to [5], wherein the base material has a maximum valley depth Sv of 2 to 15 μm.

[0014] [7] The resin product according to any one of [1] to [6], wherein the film is a plating film, a coating film or a film coating.

[0015] (Function) Even if deep and large local recesses starting from foreign substances present in the base material are reflected in the film and deep recesses with a maximum valley depth Sv of 5 to 30 times the arithmetic mean height Sa are formed in the film (see Fig. 1), since the arithmetic mean height Sa of the film is 0.2 μm or more and the skewness Ssk is -1.3 or more, the deep recesses of the film become less conspicuous and are difficult to recognize with the naked eye (see Fig. 2(a) left and right). Thereby, even when the base material is molded from recycled resin containing foreign substances, since the recesses of the film are not conspicuous, it is possible to obtain a resin product that does not cause appearance defects, and it can also be applied to resin products that require designability. On the other hand, as shown in Fig. 3, when the Sa of the film is less than 0.2 μm, regardless of the Ssk, the deep recesses of the film are conspicuous and are easy to recognize with the naked eye. Also, even when the Sa of the film is 0.2 μm or more, if the Ssk is less than -1.3, the deep recesses of the film are conspicuous and are easy to recognize with the naked eye, and such films are limited (such as samples 16, 17, 19, 20 described later), so it is also difficult to select.

Effect of the Invention

[0016] According to the present invention, even if there are deep and large local recesses starting from foreign substances on the surface of a substrate molded with a resin containing foreign substances, the recesses generated in the film due to the reflection of the local recesses are made inconspicuous and difficult to recognize with the naked eye, and a resin product that does not cause poor appearance can be obtained.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0018] 1. Substrate The resin is not particularly limited, and examples thereof include polypropylene (PP), acrylonitrile-butadiene-styrene copolymer (ABS), polycarbonate (PC), polyethylene terephthalate (PET), and the like. When the resin is recycled resin containing foreign substances, the present invention can use recycled resin without overly strengthening the selection of foreign substances, and is particularly useful in that the cost and energy do not increase. (Range of foreign substances) Foreign substances are all those that are incompatible with the resin of the substrate, and examples thereof include polyurethane (PU), nylon, coating pieces (resin, metal), and the like. The size and shape of the foreign substances are not particularly limited, and those having a major axis of 20 to 250 μm can be exemplified. The ratio of foreign matter is not particularly limited, and examples thereof include 10 vol% or less. (Range of local recess starting from foreign matter) The dimensional shape of the local recess is not particularly limited, and examples thereof include those having a major axis of 40 to 450 μm and a maximum valley depth Sv of 2 to 15 μm. The present invention is particularly useful when the Sv of the base material is 5 μm or more, and can also be applied when it is 10 to 15 μm. (Molding of base material) The molding of the base material is not particularly limited, and examples thereof include injection molding, blow molding, extrusion molding, vacuum molding, pressure air molding, slush molding, etc.

[0019] 2. Coating The type of the coating is not particularly limited, and examples thereof include plating coatings, painting coatings, film coatings, etc. · The material of the plating coating is not particularly limited, and examples thereof include copper, nickel, chromium, alloys thereof, etc. The thickness of the plating coating is not particularly limited, but is preferably 5 to 100 μm. · The material of the painting coating is not particularly limited, and examples thereof include acrylic resins, urethane resins, silicone resins, etc. The thickness of the painting coating is not particularly limited, but is preferably 5 to 100 μm. · The material of the film coating is not particularly limited, and examples thereof include PMMA, PC, PP, PVC, PET, TPU, etc. The thickness of the film coating is not particularly limited, but is preferably 20 to 300 μm.

[0020] 3. Other layers A primer layer may be provided between the base material and the coating. A protective layer may be provided on the coating.

[0021] 4. Resin products The resin products are not particularly limited, and examples thereof include automotive interior parts (instrument panel, cowl, console, glove box, door trim, pillar trim, etc.), automotive exterior parts (bumper, radiator grille, fender, emblem), home appliance cases, etc.

Example

[0022] Sample 1 consisting only of a substrate molded from recycled resin and Samples 2 to 20 of resin products composed of a substrate molded from recycled resin and a film were prepared as shown in Table 1 below.

[0023]

Table 1

[0024] · Sample 1 consists only of a 60 mm × 60 mm × 2 mm thick plate-shaped substrate injection-molded from recycled ABS. For the recycled ABS, resin products used in automobiles and home appliances were pulverized, and the ABS was selected from the pulverized material by specific gravity separation or electrostatic separation. Fig. 1 is a photograph of the surface of the substrate of Sample 1, and there are deep and large local recesses starting from foreign matters.

[0025] · Samples 2 to 6 are those in which a plating film is coated on the surface of the same substrate as that of Sample 1. The plating film of Sample 2 is a bright Cu plating film formed by electrolytic plating using a bright Cu plating solution typified by CU-BRITE EP-30 manufactured by JCU Co., Ltd. The plating films of Samples 3 to 5 are satin Cu plating films formed by electrolytic plating using a Cu plating solution in a sulfuric acid bath (200 g / L of copper sulfate, 50 g / L of sulfuric acid, 50 g / L of chloride ions) without a brightener. The surface roughness of the plating film was adjusted by changing the current density during electrolytic plating. The plating film of Sample 6 is a satin Ni plating film formed by electrolytic plating using a Ni plating solution in a barrel satin bath.

[0026] · Samples 7 to 12 are those in which a coating film is coated on the surface of the same substrate as that of Sample 1. The painted films of Samples 7 to 9 are matte painted films formed by spray coating a matte finish exterior paint typified by Reklack 30M Black manufactured by Fujikura Kasei Co., Ltd. The surface roughness of the painted film was adjusted by changing the film thickness and the pigment composition. The painted films of Samples 10 to 11 are glossy painted films formed by spray coating a glossy finish exterior paint typified by Soflex 900 Clear manufactured by Kansai Paint Co., Ltd. The surface roughness of the painted film was adjusted by the presence or absence of a primer layer. The painted film of Sample 12 is a metallic painted film formed by spray coating a metallic finish exterior paint typified by EcoNet PP-100 manufactured by ORIGIN Co., Ltd.

[0027] · Samples 13 to 16 consist only of a 60 mm × 60 mm × 2 mm thick plate-shaped substrate injection molded from recycled PP. For the recycled PP, resin products used in automobiles and home appliances were crushed, and the PP was selected from the crushed material by specific gravity separation or electrostatic separation. The painted film of Sample 13 is a metallic painted film formed by coating in the same manner as Sample 12. The painted films of Samples 14 to 16 are metallic painted films formed by spray coating a metallic finish exterior paint typified by Soflex 5800 manufactured by Kansai Paint Co., Ltd. The surface roughness of the painted film was adjusted by changing the film thickness and the composition of the bright pigment.

[0028] · Samples 17 to 18 are those in which a film coating is applied to the surface of the same substrate as that used for Samples 13 to 16. The film coating of Sample 17 is a film coating formed by heat-pressure bonding a PMMA-based decorative film. The film coating of Sample 18 is a film coating formed by heat-pressure bonding the same film as that of Sample 17 with surface embossing.

[0029] · Samples 19 to 20 are those in which a film coating is applied to the surface of the same substrate as that used for Sample 1. The film coating of Sample 19 is a film coating formed by bonding a PET-based decorative film through heat and pressure lamination for coating. The film coating of Sample 20 is a film coating formed in the same manner as Sample 17.

[0030] Also, for comparison with recycled resins, Sample 21 consisting only of a base material molded from virgin resin shown in Table 2 below, and Samples 22 - 23 of resin products composed of a base material molded from the virgin resin and a film were produced.

[0031]

Table 2

[0032] · Sample 21 consists only of a 60 mm × 60 mm × 2 mm thick plate-shaped base material injection molded from virgin ABS. · The plating film of Sample 22 is a bright Cu plating film formed by electrolytic plating using the same Cu plating solution as Sample 2 for coating. · The painted film of Sample 23 is a matte painted film formed by coating in the same manner as Sample 10.

[0033] For the base materials of Sample 1 and the films of Samples 2 - 20, the surface roughness and glossiness were measured as follows, and a visual evaluation of the appearance was made. The results are shown in Table 1. Also, for the base material of Sample 21 and the films of Samples 22 - 23, the surface roughness (only Sv) was measured as follows. The results are shown in Table 2.

[0034] <1>Measurement of surface roughness <1 - 1>Sa and Ssk Using a laser microscope (OLYMPUS LEXT OLS4100) as the measuring device, Sa and Ssk were measured and calculated under the following measurement conditions and calculation conditions. (Measurement conditions) Objective lens 50 times (MPLAPON50x LEXT, numerical aperture (NA 0.95)) Scanning area: A 258 μm × 258 μm area that does not contain recesses with a valley depth of more than 5 times that of Sa, as shown in Fig. 2(b) (the cross-sectional view is on the upper side). Average value measured at 3 or more points per sample (Calculation conditions) Cutoff: None for both λc and λf Measurement pretreatment: Perform surface correction

[0035] <1-2>Sv Using a laser microscope (OLYMPUS LEXT OLS4100) as the measurement device, Sv was measured and calculated under the following measurement conditions and calculation conditions. (Measurement conditions) Objective lens: 20x (MPLAPON20x LEXT numerical aperture (NA 0.60)) Scanning area: A 646 × 646 μm area that contains recesses with a valley depth of more than 5 times that of Sa, as shown in Fig. 2(b) (the cross-sectional view is on the lower side). Average value measured at 3 or more points per sample (Calculation conditions) Cutoff: None for both λc and λf Measurement pretreatment: Perform surface correction

[0036] <2>Measurement of glossiness (85° gloss value) Using a gloss meter (Konica Minolta MULTIGLOSS268Plus) as the measurement device, the glossiness (85° gloss value) was measured under the following measurement conditions. (Measurement conditions) Incident optical axis: 85° Average value measured at 3 or more points per sample

[0037] (3) Visual evaluation of appearance Observed visually indoors under fluorescent light, with the eyes approximately 50 cm away from the sample, and judged as follows based on the presence and degree of defects such as recesses reflecting local recesses starting from foreign substances on the surface of the film, roughness, and pits. (Judgment conditions) 〇: No defects, no problem with appearance △: Some defects are visible, but generally no problem with appearance ×: Many defects are observed, and there are problems with the appearance (Appearance score) Assign 3 points for 〇, 2 points for △, and 1 point for ×

[0038] <Consideration> As shown in Table 2, the substrate of Sample 21 molded with virgin ABS had an Sv of 0.51 μm, while the substrate of Sample 1 molded with recycled ABS had a significantly larger Sv of 9.81 μm due to the presence of local recesses starting from foreign substances. Also, in the comparison between Sample 22 and Sample 2, where a shiny Cu plating film was coated on these substrates, Sample 22 had an Sv of 0.28 μm, while Sample 2 had a significantly larger Sv of 3.64 μm. Also, in the comparison between Sample 23 and Sample 10, where a painted film with gloss was coated on these substrates, Sample 23 had an Sv of 0.09 μm, while Sample 10 had a significantly larger Sv of 1.05 μm. This indicates that the local recesses of the substrate molded with virgin ABS were reflected in the recesses of the film.

[0039] Since the Sv / Sa of Sample 3 is 24.63, it is estimated that the Sv / Sa of Samples 4 - 6 is within the range of 5 - 30. Since the Sv / Sa of Sample 7 is 7.18, it is estimated that the Sv / Sa of Samples 8 and 9 is within the range of 5 - 30. Since the Sv / Sa of Sample 13 is 15.03, it is estimated that the Sv / Sa of Samples 14 and 15 is within the range of 5 - 30. The Sv / Sa of Sample 18 is 5.02.

[0040] Figure 4 is a graph plotting Sa and Ssk of Samples 1 - 20. Samples (Samples 3 - 9, 12 - 15, 18) with a film Sa of 0.2 μm or more and an Ssk of -1.3 or more have a macroscopic visual evaluation of △ or ○ for the appearance and are positioned as examples. Samples (Samples 4, 5, 7 - 9, 12 - 14, 18) with a film Sa of 0.4 μm or more and an Ssk of -0.21 or more have a macroscopic visual evaluation of ○ for the appearance and are particularly preferable. Fig. 5 is a graph plotting the 85° gloss values and appearance scores of Samples 1 to 20. For samples where the 85° gloss value of the film is 90 or less, the visual evaluation of the appearance is Δ or ○, and the appearance score is 2 or 3. In particular, for samples where the 85° gloss value of the film is 70 or less, the visual evaluation of the appearance is ○, and the appearance score is 3, which is preferable.

[0041] Note that the present invention is not limited to the above embodiments, and can be appropriately modified and embodied without departing from the spirit of the invention.

Claims

1. It includes a substrate formed of resin and a film coated on the surface of the substrate, The film is a resin product with an arithmetic mean height Sa of 0.2 μm or more, a skewness Ssk of -1.3 or more, and a maximum valley depth Sv that is 5 to 30 times the arithmetic mean height Sa.

2. The resin product according to Claim 1, wherein the arithmetic mean height Sa is 0.4 μm or more and the skewness Ssk is -0.21 or more.

3. The resin product according to Claim 1, wherein the 85° gloss value of the film is 90 or less.

4. The resin product according to Claim 1, wherein the 85° gloss value of the film is 70 or less.

5. The resin product according to any one of Claims 1 to 4, wherein the resin is a recycled resin.

6. The resin product according to any one of Claims 1 to 4, wherein the substrate has a maximum valley depth Sv of 2 to 15 μm.

7. The resin product according to any one of Claims 1 to 4, wherein the film is a plating film, a coating film, or a film coating.

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