JP2022095052A - Molded products, electronic devices, and methods for manufacturing molded products - Google Patents

Abstract

An object of the present invention is to provide a molded article with high appearance quality. A first area having, on the surface, a gloss pattern consisting of a first area that is a low gloss area and a second area that is a high gloss area having a higher glossiness than the low gloss area; a second area having a height higher than that of the first area; and a height of the second area being higher than that of the first area. lower than the height of the second region in the area of and between the first region and the second region, both the glossiness of the first region and the glossiness of the second region It is characterized by having a third region with a different degree. [Selection drawing] Fig. 3

Description

The present invention relates to a molded product having a design on the surface, an electronic device, and a method for manufacturing the molded product.

High design is required for the appearance of resin molded products used for housings of electronic devices such as printers, cameras, and interchangeable lenses, and outer shells. For example, there is one having a texture of leather tone coating characterized by having unevenness on the surface imitating a natural leather grain and having a high gloss of the convex portion as compared with the concave portion. Further, by forming a surface pattern composed of a flat glossy surface and a non-glossy surface having a convex portion protruding from the surface on the appearance surface, both aesthetics and stains such as fingerprints are less noticeable. There is also.

When a resin molded product having the above-mentioned uneven structure or convex portion is manufactured by injection molding or the like, the outer surface of the resin molded product may include a plurality of surfaces having different angles with respect to the mold release direction. Various restrictions may be required for the uneven structure to be provided. For example, on a component surface that is inclined with respect to the mold release direction or is composed of a curved surface, in order to improve the mold releasability, it is possible to avoid so-called undercuts in the uneven structure. Will need to be done. Therefore, it may be unavoidable to omit the uneven structure for a part of the appearance surface of the resin molded product. On the other hand, a technique disclosed in Patent Document 1 is known as a technique for suppressing a deterioration in design appearance quality due to omission of a concave-convex structure. In Patent Document 1, the unevenness of the appearance surface is reduced to a step that can be released, and the gloss pattern is maintained, thereby achieving both releasability and appearance quality.

Japanese Unexamined Patent Publication No. 2020-40381

In the prior art, depending on the combination of the shape of the appearance surface of the resin molded product and the observation conditions, there may be a difference in the visual impression between the region where the unevenness is not reduced and the region where the unevenness is reduced. This is because if the step of the unevenness is reduced, the shadow caused by the unevenness is also reduced. For example, when the exterior surface is illuminated from a certain direction, a shadow of the convex portion is generated in the concave portion (flat portion), and a part of the side surface of the convex portion becomes a shadow and becomes dark. The area of these shadows and the area of the side surface of the convex portion including the shadow become smaller as the step of the unevenness becomes smaller. When the external surface is viewed from its normal direction (that is, from the front) or illuminated, the shadows that occur even if the unevenness is large and the area of the visible side surface is small, so the above-mentioned changes in shadows Is hard to see and there is no difference in impression. However, when viewed from an angle or illuminated with respect to the normal direction of the appearance surface, changes in shadows may be visually recognized, and the impression may be perceived differently.

Therefore, an object of the present invention is to provide a resin molded product having higher appearance quality.

The molded product of the present invention has a first area having a first region and a second region on the surface, the height of the second region being higher than the height of the first region, and the second region. The height of the region includes a second area whose height is lower than the height of the second region of the first area, and the second area is between the first region and the second region. In addition, it is characterized by having a third region having a glossiness different from that of both the glossiness of the first region and the glossiness of the second region.

The electronic device of the present invention is characterized by comprising the above-mentioned molded product.

The method for manufacturing a molded product of the present invention is a method for manufacturing a molded product using a mold, and the second region comprises a first region and a second region on the surface thereof. Includes a first area where the height of the first region is higher than the height of the first region, and a second area where the height of the second region is lower than the height of the second region of the first area. In the second area, the glossiness of the first region and the glossiness of the second region are different between the first region and the second region. It is characterized by having a step of injecting a resin into a mold having the region of No. 1 and molding a molded product.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a molded product having high appearance quality.

The perspective view which showed the appearance of the printer as the electronic device which concerns on embodiment of this invention. The schematic diagram which showed the structure of the resin molded article which concerns on embodiment of this invention. The figure explaining the pseudo shadow part which concerns on embodiment of this invention. The schematic diagram which shows an example of the manufacturing apparatus which processes the mold for manufacturing the resin molded article which concerns on embodiment of this invention. The figure explaining the processing process of the mold for manufacturing the resin molded article which concerns on embodiment of this invention. The figure explaining the resin molded article which concerns on Example 1. FIG. The figure explaining the third area. The figure explaining the manufacturing method which concerns on embodiment of this invention. The perspective view which showed the appearance of the camera as the electronic device which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The numerical values taken up in the following embodiments are reference numerical values and do not limit the present invention.

(Form for carrying out the invention)
FIG. 1 is an external view of an electronic device, particularly a printer, which is an example of an article having a resin molded product according to the present invention. In FIG. 1, the printer 1 is, for example, a composite printer, and the original cover 12, the outer surface (exterior surface) of the housing 10, and the like are molded of a predetermined color, for example, black resin. The outer surface 11 of the printer 1 is a portion that is easily visible to the user and requires a high-quality appearance, and has an uneven pattern (a pattern expressed by undulations on the surface) and a gloss pattern (a pattern expressed by a change in gloss). A surface pattern consisting of a combination of these is formed. In the present embodiment, an example of molding a surface pattern having a texture of leather tone coating, which is composed of an uneven pattern imitating a leather grain and a gloss pattern associated with the unevenness, is shown.

FIG. 2 shows an example of the outer surface 11 of the document cover 12 in the present embodiment. 2 (A) is an overall plan view of the outer surface 11, FIG. 2 (B) is an enlarged view of the region 22 of FIG. 2 (A), and FIG. 2 (C) is along the broken line PP'of FIG. 2 (B). The cross-sectional structure is shown.

The outer surface 11 of FIG. 2A is composed of a first area (for example, a flat surface portion) 20 and a second area (for example, a curved surface portion inclined with respect to the flat surface portion) 21. As shown in FIGS. 2B and 2C, the uneven pattern and the gloss pattern are both formed in the first area 20, and the flat portion 27 is provided with the low gloss portion 24 as the first region. A high gloss portion 23 as a second region is provided on the top portion (upper surface portion) of the convex portion 26. Further, the uneven pattern and the gloss pattern are formed on the entire surface of the first area 20 shown in FIG. 2 (A).

On the other hand, in the second area (for example, the curved surface portion 21), the mold is formed so as not to be undercut in the mold release direction (upward direction in FIG. 2C), for example. That is, only the gloss pattern is molded (the uneven pattern is not formed), or the uneven pattern having the convex portion lower than the convex portion of the uneven pattern in the first area is formed. In other words, the first area, which is composed of a first region (low gloss portion) and a second region (high gloss portion), in which the height of the second region is higher than the height of the first region. It has a second area where the height of the second region is lower than the height of the second region of the first area. (In the present specification, even when the heights of the first region and the second region are equal in the second area (only the gloss pattern is molded (the uneven pattern is not molded)), the height of the second region is also formed. It is said that the height is lower than the height of the second region of the first area.)

Therefore, the second area 21 does not have shadows due to the uneven pattern, or only in a very small area. Therefore, it is assumed that a gloss pattern similar to that of the first area 20 (for example, a gloss pattern consisting of only a high gloss portion 23 and a low gloss portion 24) is formed in the second area 21 by a conventional method. Then, as described above, the appearance of the second area 21 may be different from the appearance of the first area 20 depending on the observation conditions. On the other hand, in the present embodiment, in order to compensate for the shadow caused by the uneven pattern, the gloss pattern of the second area 21 is the low gloss portion 24 (first region) and the high gloss portion 23 (second region). ), A pseudo-shadow portion 25 as a third region is provided at the boundary portion. In the present specification, the pseudo-shadow portion may be referred to as an antiglare portion. In the present embodiment, the pseudo-shadow portion 25 has a shape that imitates the shadow generated on the outer surface 11 when the high-gloss portion 23 is a convex portion, and has a gloss different from that of the high-gloss portion 23 and the low-gloss portion 24. have. In general, when the same resin material is used to form surfaces that differ only in gloss, they are perceived with different brightness under most observation conditions, except in very limited specific cases. Therefore, the brightness of the pseudo-shadow portion 25 looks different from that of the low-gloss portion 24 (first region) and the high-gloss portion 23 (second region), and the high-gloss portion 23 and the low-gloss portion sandwiching the pseudo-shadow portion 25. It is an illusion that there is a step between it and 24. As a result, the first area 20 and the second area 21 have almost the same visual impression. In the present embodiment, an example in which the first area is, for example, a flat surface portion and the second area is, for example, a curved surface portion is shown, but the present invention is not limited to this. Both the first area and the second area may be a flat surface portion, and both the first area and the second area may be a curved surface portion.

In the present embodiment, the high-gloss portion 23, the low-gloss portion 24, and the pseudo-shadow portion (anti-glare portion) 25 are formed by imparting different surface roughness to the outer surface 11. Further, the pseudo-shadow portion 25 has a lower gloss than the low gloss portion 24. In the example of FIG. 2C, a smooth surface (for example, a glossiness Gs (60 °) of 10 gloss units or more and 20 gloss units or less) is formed on the high gloss portion 23 so that the incident light is specularly reflected. There is. Further, the low gloss portion 24 is formed with fine irregularities that are difficult to visually recognize so that the incident light is scattered (for example, the glossiness Gs (60 °) is 5 gloss units or more and 10 gloss units or less). Further, the pseudo-shadow portion (anti-glare portion) 25 is formed with fine irregularities having a surface roughness coarser than that of the low-gloss portion 24 (for example, the glossiness Gs (60 °) is 1 gloss unit or more and 5 gloss units or less). ). Here, the fine unevenness of the low gloss portion 24 and the pseudo-shadow portion 25 is a concave-convex structure having a sufficiently small height difference that does not cause undercut. The surface roughness of the first region is preferably 0.5 μm or more and less than 1.2 μm in RMS value. Further, the surface roughness of the second region is preferably less than 0.5 μm in RMS value. Further, the surface roughness of the third region is preferably 1.2 μm or more in terms of RMS value.

Further, in the present embodiment, as shown in FIG. 3, a region corresponding to a shadow under a specific observation condition when the high gloss portion 23 is a convex portion is imparted to the gloss pattern as a pseudo shadow portion 25. do. 3 (A) and 3 (B) are perspective views and side views of the convex portion 28 and the region in the vicinity thereof, assuming that the high gloss portion 23 is provided with the virtual convex portion 28. 3 (C) is a front view showing a gloss pattern corresponding to this region. First, as shown in FIGS. 3A and 3B, the shadow of the convex portion 28 generated when a specific light source direction L is assumed is calculated. Specifically, the apparent width d when observed in the direction of the line-of-sight direction E from the predetermined viewpoint position e ₀ is based on the height of the convex portion 28, the light source direction L, the viewpoint position e ₀ , and the line-of-sight direction E. calculate. Next, as shown in FIG. 3C, a pseudo-shadow portion 25 is provided on the gloss pattern so that the width becomes d, starting from the contour of the high gloss portion 23 corresponding to the convex portion 28. The width referred to here is a length measured along the direction L'projected on the gloss pattern of the light source direction L. The method of imparting the pseudo-shadow portion 25 is not limited to the method described above. For example, as the shadow of the convex portion 28, a shadow considering a plurality of light sources and mutual reflection may be calculated by using a known computer graphics technique. Alternatively, as a simpler method, from the region obtained by translating the high-gloss portion 23 in a predetermined direction by a predetermined distance on the gloss pattern, the overlapping portion with the high-gloss portion 23 before the parallel movement is removed. The area may be a pseudo-shadow portion 25. That is, the pseudo-shadow portion 25 may be provided so as to be in contact with the high-gloss portion 23 and overlap with the low-gloss portion 24. If the pseudo-shadow portion in the present invention is arranged so as to have an illusion that there is a concavo-convex pattern having a convex portion at the height of the convex portion of the concavo-convex pattern formed in the first area on the surface. Well, the physical correctness as a shadow is not essential.

In the leather tone surface pattern realized in the present embodiment, it is preferable that the convex portion 26 is raised in a range of 1 μm or more and less than 100 μm from the flat portion 27. The height difference between the convex portion 26 and the flat portion 27 is measured by measuring the height of the high gloss portion 23 using, for example, a white interferometer, with reference to the low gloss portion 24 corresponding to the base surface of the flat portion 20. can. In the present embodiment, this height difference is an average value of values measured at 10 points in a 1.0 mm × 1.0 mm region of the molded product with a 10x objective lens using a 3D optical profiler NewView7000 manufactured by ZYGO. Evaluated in. The heights of the plurality of convex portions 26 provided on the entire surface of the flat surface portion 20 do not necessarily have to be uniform, and may be different for each convex portion. Further, the height in one convex portion does not necessarily have to be constant, and there may be a distribution of a high portion or a low portion in the convex portion.

Further, the difference in gloss between the high gloss portion 23, the low gloss portion 24, and the pseudo-shadow portion 25 may be such that the difference can be visually recognized, but preferably there is a difference of 5 or more in glossiness between the portions. Is desirable. The glossiness in the present specification is a value (Gs (60 °)) measured using a gloss meter based on the mirror glossiness of JIS Z 8741 with a reflection angle of 60 °. The glossiness can be measured, for example, by using a 60-degree glossiness meter IQ FLEX60 manufactured by Rhopoint Instruments. In addition, the glossiness measurement with the same device requires an area of several millimeters square or more. For example, when measuring the glossiness of a high gloss part, a sample in which only the high gloss part is formed in an area of 20 mm square is used. Measurement is possible by preparing. The glossiness of the low-gloss portion and the pseudo-shadow portion can be measured by preparing a sample in the same manner.

Further, it is preferable that the fine unevenness for realizing the low gloss portion 24 and the pseudo-shadow portion 25 is formed with a step of 15 μm or less. This is because fine irregularities of 15 μm or less cannot be visually recognized as irregularities by the observer, and due to the shrinkage rate of the resin during injection molding and the elasticity of the resin, the structure is destroyed even in the undercut direction. This is because the mold can be released satisfactorily. According to the experiments by the inventors, ABS or HIPS (high impact polystyrene) is used if the maximum step in the direction orthogonal to the mold release direction is 15 μm or less for a 100 mm wide semi-cylindrical resin molded product. It has been confirmed that mold release is possible without difficulty with resins such as.

Next, a method for manufacturing the resin molded product according to the present embodiment will be described.

The resin molded product according to the present embodiment can be injection-molded, for example, by injecting and filling the cavity formed in the mold with the resin from the gate, which will be described in detail later. FIG. 4 shows a configuration of a machining center for processing a mold for molding a resin molded product according to the present embodiment. The machining center 90 of FIG. 4 includes a processing machine main body 91 and a control device 92. The cavity may be formed by a plurality of pieces (cavity pieces) that form a part of the mold. By forming the cavity with the pieces in this way, even if the molded product has a complicated shape, the transfer surface can be divided and processed, so that the manufacturing cost of the mold can be reduced. The processing machine main body 91 manufactures a mold by cutting a mold (cavity piece) 93, which is an object to be processed. The processing machine main body 91 has a spindle 95, an X stage 96, a Y stage 97, and a Z stage 98, which are spindles that support the cutting tool 94. As the cutting tool 94, an end mill can be preferably used. The spindle 95 rotates the cutting tool 94 around the Z axis. The Z stage 98 supports the spindle 95 and moves the cutting tool 94 in the Z direction with respect to the mold 93. Similarly, the X stage 96 moves the cutting tool 94 with respect to the mold 93 in the X direction, and the Y stage 97 moves the cutting tool 94 in the Y direction. With such a configuration, the processing machine main body 91 can move the tip of the cutting tool 94 in the XYZ direction relative to the mold 93 while rotating the cutting tool 94. The control device 92 is composed of a computer having a CPU, a memory, and the like, and controls the processing machine main body 91 according to NC data 99. The NC data 99 includes cutting processes such as the amount of movement in the X direction, the amount of movement in the Y direction, the amount of movement in the Z direction, the rotation speed of the spindle, the feed speed in the X direction, the feed speed in the Y direction, and the movement speed in the Z direction. Contains various instructions used in. Under the control of the control device 92, the cutting tool 94 can be rotated and moved relative to the mold 93 to cut a three-dimensional shape based on NC data 99 on the mold 93.

FIG. 5 shows the first molding surface and the second molding of the mold 93 for molding the first area (flat surface portion) 20 and the second area (curved surface portion) 21 of the resin molded product of the present embodiment, respectively. The manufacturing process of the surface is shown. As shown in this figure, the transfer pattern that transfers the surface patterns of the first area (flat surface portion) 20 and the second area (curved surface portion) 21 described above is the first molding surface and the first molding surface of the mold 93. It is processed into the molding surface of 2. Note that FIG. 5 shows an example in which the second area (curved surface portion) 21 is a convex surface as shown in FIG. 2 (C).

In the first mold processing step shown in FIG. 5A, the surface 101 of the mold 93 is rough-processed. A radius end mill 102 is used as a cutting tool in the machining center of FIG. 4, and the radius end mill 102 is cut while rotating based on NC data 99, scanned, and cutting is performed on the mold surface.

In the second mold processing step shown in FIG. 5B, a ball end mill 103 is used to process fine irregularities on the surface 101 of the mold 93. The ball end mill 103 is scanned against the mold region for forming the second area (curved surface portion) 21 described above, and a plurality of recesses 104 are machined on the surface including at least the region corresponding to the pseudo-shadow portion 25. As a result, fine irregularities are formed on the surface of the mold region for forming the second area (curved surface portion) 21.

In the third mold processing step shown in FIG. 5C, the surface 101 of the mold 93 is smoothly processed. Based on the NC data 99, the ball end mill 103 is cut into the mold region other than the above-mentioned pseudo-shadow portion 25 while rotating, and the surface is smoothed by scanning. Here, the fine unevenness composed of the concave portions 104 that were not smoothed (that is, remained without being scraped) becomes the fine unevenness constituting the pseudo-shadow portion 25 when transferred to the resin molded product by injection molding.

In the fourth mold processing step shown in FIG. 5D, unevenness is processed on the surface 101 of the mold 93 by using a ball end mill 103. Based on NC data 99, the ball end mill 103 is cut into the mold region for forming the first area (flat surface portion) 20 while rotating, and is scanned to form the recess 105. The concave portion 105 is a region that becomes a convex portion 26 when transferred to a resin molded product.

In the fifth mold processing step shown in FIG. 5 (E), a ball end mill 103 is used on the surface 101 of the mold 93 to process fine irregularities different from those in the second mold processing step. A plurality of recesses 106 are machined on the surface of the region corresponding to the low gloss portion 24 of both the first area (flat surface portion) 20 and the second area (curved surface portion) 21. Here, the recess 104 and the recess 106 are processed so that one or more of the density, the depth, and the size are different. Thereby, the surface roughness can be made different between the fine unevenness formed of the concave portion 104 and the fine unevenness formed of the concave portion 106. When the fine unevenness composed of the concave portion 106 is transferred to the resin molded product by injection molding, it becomes the fine unevenness constituting the low gloss portion 24.

As a result of performing the above mold processing step, the region where neither the recess 104 nor the recess 106 is formed becomes the high gloss portion 23.

Examples of the material of the mold 93 for performing the mold processing as described above include stainless steel, but any other material can be used from the viewpoint of workability and durability of injection molding.

Further, although an example of processing the mold related to the resin molded product of the present embodiment by cutting is shown here, the processing method of the mold is not limited to this. Needless to say, the mold may be manufactured by using another processing method such as a laser processing machine.

Next, in the embodiment, a method of manufacturing a resin molded product using the above-mentioned mold will be described. 8 (a) to 8 (e) are schematic views for explaining a manufacturing process when manufacturing a resin molded product according to an embodiment using an injection molding machine.

FIG. 8A is a schematic view showing the setup of the injection molding apparatus, where 81 and 82 are molds, 83 is a cylindrical cylinder for injecting resin into the mold, and 84 is a cylinder made of resin material. It is a part called a hopper for throwing into the inside of. Is formed on the molding surface of the mold 81 and / or the mold 82. In this embodiment, as the resin material, a polycarbonate resin (colored black) mixed with about 30% of glass filler was used.

There is a screw (not shown) inside the cylinder 83, which is rotated by a motor 85 to feed the resin material to the tip of the cylinder 63. Further, the cylinder 83 is provided with a heater (not shown), and the solid resin material charged from the hopper 84 is heated to a melting temperature or higher while being sent to the tip of the cylinder and melted, and the tip of the cylinder 83 is melted. It is stored in the space of the part.

Next, the mold clamping step shown in FIG. 8 (b) is performed. The mold 81 and the mold 82 are aligned and closed by a movable mechanism (not shown) to form a cavity. Further, the mold 81 and the mold 82 are heated by a heater (not shown). Generally, a flow path through which a high-temperature liquid flows is formed inside the mold, and the flow rate and temperature of the liquid are controlled to adjust the temperature of the mold. The heating temperature of the mold in this step is called the mold temperature.

Subsequently, the injection step shown in FIG. 8C is performed. The nozzle at the tip of the cylinder 83 is pressed against the injection hole portion provided in the mold 82. Further, the motor 85 operates and rotates a screw (not shown) to inject the molten resin 86 into the cavity formed by the mold 81 and the mold 82. The temperature of the molten resin in this step is referred to as a resin temperature.

Subsequently, the pressure holding step and the cooling step shown in FIG. 8D are performed. In the pressure holding step, the pressure applied to the molten resin 86 injected into the cavity is kept at a predetermined value by controlling the hydraulic pressure in the cylinder 83. The pressure of this predetermined magnitude is called holding pressure. The holding pressure is selected so that the molten resin 86 spreads to every corner of the space inside the cavity. That is, the resin is filled into the unevenness of the molding surface of the mold without any gap. Then, the transfer pattern for transferring the surface patterns of the first area (flat surface portion) 20 and the second area (curved surface portion) 21 processed into the mold is appropriately transferred to the resin with high shape accuracy. Holding pressure is applied to the molten resin.

In the cooling step following the pressure holding step, the mold 81 and the mold 82 are cooled by a cooling mechanism (not shown) while keeping the arrangement shown in FIG. 8 (d), and the resin inside the cavity is cooled to the temperature below the glass transition point temperature. , Solidify. As the cooling mechanism, for example, a method in which a flow path of the refrigerant is arranged around the mold and the refrigerant is circulated to cool the mold can be used.

After the resin in the cavity has solidified, the mold opening step and the mold release step shown in FIG. 8 (e) are performed. First, in the mold opening step, the mold 81 and / or the mold 82 is moved by a drive mechanism (not shown) to separate them from each other.

In the subsequent mold release step, for example, by projecting an ejector pin (not shown), the resin molded product 87 adhering to one mold is peeled off from the mold and taken out. If necessary, the gate marks (burrs left at the injection gate position) formed on the removed resin molded product 87 may be removed.

By the manufacturing method described above, in the present embodiment, a transfer pattern for transferring the surface patterns of the first area (flat surface portion) 20 and the second area (curved surface portion) 21 is formed on the outer surface with high shape accuracy. A resin molded product can be manufactured.

The molding of the resin molded product by injection molding and the manufacturing process of the mold have been described above, but the manufacturing method is not limited to the above. The molding of the resin molded product provided with the first area (for example, a flat surface portion) 20 and the second area (for example, a curved surface portion) 21 as described above may be performed by an appropriate method other than the above-mentioned injection molding. Hereinafter, more specific examples will be described with respect to the present embodiment. However, in the following, the same reference numerals will be used for the same members, dimensions, directions, etc., and detailed description thereof will be omitted.

The article having the resin molded product according to the present invention is not limited to the printer shown in FIG. According to the present invention, the surface pattern of the present invention can be imparted to a resin molded product having various forms and functions.

For example, the surface pattern of the present invention can be imparted to the surface of the exterior component 121 of the camera body, the exterior component 122 of the lens barrel, and the like of the camera shown in FIG. The camera is not limited to the example shown in FIG. 9, and may be an interchangeable lens single-lens reflex camera, a mirrorless camera, a compact camera, or a smart phone having a shooting function.

Further, the printer is not limited to the example shown in FIG. 1, and can be applied to various forms such as a printing-only machine, a copying machine, and a multifunction device with a reading function, and the recording method includes an electrophotographic type, an inkjet type, and a thermal transfer type. , There is no particular limitation.

Further, the present invention can be applied not only to resin molded products of cameras and printers, but also to resin molded products in which an observer wants to visually recognize a brilliant feeling, such as an interior part of an automobile and an outer box of cosmetics. The resin molded product may have a thin flat plate shape such as a sheet or a film, a three-dimensional shape having a curved surface, or may have flexibility.

6 (A) to 6 (C) are views showing the resin molded product according to the first embodiment. 6 (A) shows a plan view showing a height distribution, FIG. 6 (B) shows a plan view showing a gloss distribution, and FIG. 6 (C) shows a cross-sectional view. As shown in these figures, an uneven / glossy pattern representing the texture of the leather tone coating was formed on the plate-shaped resin molded product 60 having a thickness of 1.6 mm. The resin molded product 60 includes a flat surface portion 61 and a curved surface portion 62 provided on the edge thereof and inclined with respect to the flat surface portion 61. The radius of curvature of the curved surface portion 62 is 60 mm, and the inclination angle (θ) of the tangent line of the curved surface with respect to the flat surface portion 61 is 45 degrees at the maximum. The step of the convex portion 63 with respect to the normal direction of the flat portion 64 was set to 20 μm. For convenience of illustration, the curved surface portion 62 in FIG. 6 (A) is shown as having a height distribution of 0 μm, but as is clear from the cross-sectional view of FIG. 6 (C), the curved surface portion 62 has a maximum height difference of 4 μm. There is a pattern of fine irregularities. The pseudo-shadow portion 67 was provided with a width of 20 μm in the direction indicated by the arrow 68 in FIG. 6 (B).

In this embodiment, only the flat surface portion 61 is formed with the uneven pattern having a large height difference composed of the convex portion 63 and the flat portion 64, and the curved surface portion 62 is not formed with the uneven pattern having a large height difference. .. The gloss pattern is composed of a high gloss portion 65, a low gloss portion 66, and a pseudo-shadow portion 67, and the high gloss portion 65 and the convex portion 63 are associated with each other. Further, the pseudo-shadow portion 67 is formed only on the curved surface portion 62, and the pseudo-shadow portion 67 is not formed on the flat surface portion 61. The low gloss portion 66 was formed with fine irregularities having a height of 2 μm so that the surface roughness was RMS = 1.0 μm and the glossiness was Gs (60 °) = 7GU. The pseudo-shadow portion 67 was formed with fine irregularities having a height of 2 μm so that the surface roughness was RMS = 1.5 μm and the glossiness was Gs (60 °) = 2GU. The surface roughness of the high-gloss portion 65 without forming fine irregularities was set to RMS = 0.45 μm and the glossiness was set to Gs (60 °) = 18 GU. The cross-sectional structure of the flat surface portion 61 and the curved surface portion 62 is as shown in FIG. 6 (C).

Stainless steel was used as the material of the mold for manufacturing the resin molded product of this example, and a radius end mill was attached to the machining center shown in FIG. 4 for roughing. Then, using a ball end mill, an inverted shape of a leather tone pattern including a convex portion 63, a flat portion 64, a high gloss portion 65, a low gloss portion 66, and a pseudo shadow portion 67 was processed into a mold. Then, injection molding was performed using a mold to obtain a resin molded product 60. Although black HIPS was used as the resin material, in that case, the resin molded product 60 could be released without destroying the structure.

The outer surface of the obtained resin molded product was visually observed by an observer with standard visual acuity, and the difference in impression between the flat surface portion 61 and the curved surface portion 62 was evaluated. As a result, the difference in shadows depending on the presence or absence of unevenness may be perceived depending on the viewing angle or illumination angle, but the difference becomes less noticeable because the shadows of the unevenness are visually supplemented by the pseudo-shadow portion. It was confirmed that In particular, it was confirmed that the difference in visual impression was significantly reduced as compared with the resin molded product by the conventional method in which the pseudo-shadow portion was not formed on the curved surface portion 62.

<Other Examples>
In the embodiments and examples shown above, an example of imparting a surface pattern having the texture of leather tone coating to the outer surface of the resin molded product is shown, but the surface pattern is not limited to this. Further, the high gloss portion and the convex portion and the low gloss portion and the flat portion (concave portion) are associated with each other, but the corresponding relationship between the gloss and the unevenness is not limited to this. A surface pattern in which a low-gloss portion and a convex portion and a high-gloss portion and a concave portion are associated with each other, for example, a decorative surface expressing a specific design is expressed even in a configuration in which fine irregularities are formed on the convex portion of a resin molded product. Needless to say, you can.

Further, an example in which the pseudo-shadow portion has a lower gloss than the low-gloss portion has been described, but the gloss of the pseudo-shadow portion is not limited to this. As shown in FIG. 7 (A), the pseudo-shadow portion 71 may have a higher gloss than the high gloss portion 72, or as shown in FIG. 7 (B), the high gloss portion 72 and the low gloss portion 73. It may have a luster between them. Alternatively, as shown in FIG. 7C, the pseudo-shadow portion 71 may be formed by mixing a gloss higher than that of the high gloss portion 72 and a gloss lower than that of the low gloss portion 73.

Further, the gloss of the convex portion and the flat portion may be the same. Examples of the pseudo-shadow portion in that case are shown in FIGS. 7 (D) to 7 (F). 7 (D) shows the pseudo-shadow portion 71 having low gloss, FIG. 7 (E) shows the pseudo-shadow portion 71 having high gloss, and FIG. 7 (F) shows the pseudo-shadow portion 71 having low gloss and high gloss. This is an example of a case where and is mixed and configured.

Claims (14)

On the surface, a first area composed of a first region and a second region, the height of the second region higher than the height of the first region, and the height of the second region are the above. Including a second area lower than the height of the second area of the first area,
In the second area, the glossiness of the first region and the glossiness of the second region are different between the first region and the second region. A molded product characterized by having a region. The molded product according to claim 1, wherein the first region has a lower glossiness than the second region. The surface roughness of the first region is 0.5 μm or more and less than 1.2 μm in RMS value, and the surface roughness of the second region is less than 0.5 μm in RMS value, and the surface roughness of the third region is The molded product according to claim 1 or 2, wherein the surface roughness has an RMS value of 1.2 μm or more. The molded product according to claim 1, wherein the first region has a higher glossiness than the second region. The surface roughness of the first region is less than 0.5 μm in RMS value, the surface roughness of the second region is 0.5 μm or more and less than 1.2 μm in RMS value, and the surface roughness of the third region is The molded product according to claim 4, wherein the surface roughness has an RMS value of 1.2 μm or more. The molded product according to any one of claims 1 to 5, wherein the difference in glossiness between the first region and the third region is 5 gloss units or more at 60 degree glossiness. The molded product according to any one of claims 1 to 6, wherein the difference in glossiness between the second region and the third region is 5 gloss units or more at 60 degree glossiness. The molded product according to any one of claims 1 to 7, wherein the third region is in contact with the second region and is superimposed on the first region. An electronic device comprising the molded product according to any one of claims 1 to 8. It is a manufacturing method of a molded product that manufactures a molded product using a mold.
On the surface, a first area composed of a first region and a second region, the height of the second region higher than the height of the first region, and the height of the second region are the above. Including a second area lower than the height of the second area of the first area,
In the second area, between the first region and the second region, the glossiness of the first region and the glossiness of the second region are different from each other. A method for manufacturing a molded product, which comprises a step of injecting a resin into a mold having a region to mold the molded product. The method for producing a molded product according to claim 10, wherein the first region has a lower gloss than the second region. The surface roughness of the first region is 0.5 μm or more and less than 1.2 μm in RMS value, and the surface roughness of the second region is less than 0.5 μm in RMS value, and the surface roughness of the third region is The method for producing a molded product according to claim 10 or 11, wherein the surface roughness has an RMS value of 1.2 μm or more. The method for producing a molded product according to claim 10, wherein the first region has a higher gloss than the second region. The surface roughness of the first region is less than 0.5 μm in RMS value, the surface roughness of the second region is 0.5 μm or more and less than 1.2 μm in RMS value, and the surface roughness of the third region is The method for producing a molded product according to claim 13, wherein the surface roughness has an RMS value of 1.2 μm or more.

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