Patent Description:
A radio wave transmission cover for a vehicle is generally provided with a decorative layer for displaying various designs. The decorative layer is a relative thin layer formed by metal deposition, film transfer and the like. The radio wave transmission cover is mainly configured with a transparent resin layer of a front side and a base layer of a rear side while interposing the decorative layer between the transparent resin layer and the base layer. The radio wave transmission cover is formed to have a uniform thickness such that transmission/reception of millimeter waves is not affected.

In order to express three-dimensional characters or figures on the radio wave transmission cover, for example, a rear surface of the transparent resin layer is employed as an uneven surface having a general part and a concave part recessed with respect to the general part, a blackened print layer is formed in the general part, and then an indium layer is formed on the entire of the uneven surface by a vacuum deposition method as disclosed in <CIT>.

In the manufacturing method of the radio wave transmission cover disclosed in <CIT>, however, the indium layer covers the entire of the uneven surface of the transparent resin layer. Indium has a radio wave transmission characteristic, but when the entire surface of the transparent resin layer is covered with the indium, since the attenuation and the phase difference of radio waves of the radio wave transmission cover become large, radio wave transmission performance is reduced.

In this regard, it is considered to partially print the indium layer only in the concave part of the uneven surface of the transparent resin layer. As an indium printing method, a screen printing method, a hot stamping method and the like are considered.

However, the screen printing method is a method in which ink is pushed out from a screen mesh and is printed. When the position of the screen mesh is slightly shifted, the boundary of a print part is shifted from the boundary part of a concave part and a convex part. Since the boundary line of characters and figures of the concave part or the convex part is not clear, appearance becomes worse.

The hot stamping method is a method in which a transfer film having a sheet printed with the indium layer is arranged on the uneven surface of the transparent resin layer, and the transfer sheet is pressed to the uneven surface by using a hot stamp while heating it, so that the indium layer is transferred to the uneven surface. In this method, there may occur a transfer error such as non-attachment of the indium layer on the sheet to the uneven surface.

Furthermore, accurately forming a metal layer of indium and the like only in the concave part of the uneven surface of the transparent resin layer is an issue of the decorative member other than the radio wave transmission cover.

<CIT> discloses a resin molded article disposed on a beam path of a radio wave radar device. <CIT> discloses an exterior member for a vehicle and a front grille.

The present invention has been made to solve the above-described problem, and an object of the present invention is to provide a radio wave transmission cover for a vehicle capable of accurately forming a design on an uneven surface of a transparent resin layer and a manufacturing method thereof.

The above object is solved by a radio wave transmission cover for a vehicle according to claim <NUM> or a manufacturing method of a radio wave transmission cover for a vehicle according to claim <NUM>.

According to an aspect of the present teachings, there is provided a manufacturing method of a decorative member including: preparing a transparent resin layer provided on a rear surface thereof with a general portion, a stepped portion recessed or protrudingly provided with respect to the general portion, and an inclination portion provided between the stepped portion and the general portion, an inclination angle of the inclination portion with respect to a normal line of the general portion being equal to or more than <NUM>° and being equal to or less than <NUM>° and a width of the inclination portion being large beyond <NUM> and being equal to or less than <NUM>; disposing a first layer on at least the stepped portion and the inclination portion of the rear surface of the transparent resin layer; allowing a part covering the stepped portion in the first layer to remain and separating an excess part, other than the covering the stepped portion, in the first layer by laser irradiation; and disposing a second layer on a part not covered with at least the first layer of the rear surface of the transparent resin layer.

According to another aspect of the present teachings, there is provided a decorative member including: a transparent resin layer provided on a rear surface thereof with a general portion, a stepped portion recessed or protrudingly provided with respect to the general portion, and an inclination portion provided between the stepped portion and the general portion; and a decorative layer provided on the rear surface of the transparent resin layer, wherein: an inclination angle of the inclination portion with respect to a normal line of the general portion is equal to or more than <NUM>° and is equal to or less than <NUM>°; a width of the inclination portion is large beyond <NUM> and is equal to or less than <NUM>; and the decorative layer includes: a first layer that covers the stepped portion of the rear surface of the transparent resin layer; and a second layer that covers a part of the rear surface of the transparent resin layer, which is not covered by at least the first layer.

According to the manufacturing method of the decorative member of the present teachings, the first layer is disposed on at least the concave or convex stepped portion and the inclination portion on the rear surface of the transparent resin layer, and the part covering the stepped portion in the first layer is allowed to remain, and the excess part in the first layer, other than the part covering the stepped portion, is separated by the laser irradiation. Therefore, it is possible to accurately separate the excess part. When the first layer is viewed from the surface of the transparent resin layer, it is possible to view an accurate design.

The inclination angle of the inclination portion with respect to the normal line of the general portion is <NUM>° to <NUM>° and the width of the inclination portion is large beyond <NUM> and is equal to or less than <NUM>. The width of the inclination portion is larger than separation tolerance when the first layer is separated by the laser irradiation. Therefore, even though a molding dimensional error or a positional shift at the time of installation of a laser irradiation jig occurs in the transparent resin layer, these errors are absorbed, so that the boundary line between the first layer and the separation part, from which the excess part has been separated, can be positioned on the inclination portion. The boundary line between the first layer and the separation part is allowed to be positioned on the inclination portion, so that the boundary line is prevented from being shifted on the general portion or the stepped portion.

Since the inclination angle of the inclination portion is <NUM>° to <NUM>°, when the first layer is viewed from the surface side of the transparent resin layer, the first layer remaining on the inclination portion is difficult to be viewed. The first layer is viewed as if it covers only the stepped portion, so that it is possible to three-dimensionally view the first layer with a good appearance.

The separation of the excess part of the first layer is performed by the laser irradiation. Since the laser has a high degree of accuracy of an irradiation position, it is possible to accurately separate the excess part of the first layer. Therefore, according to the present teachings, as compared with the case in which the first layer has been formed on the stepped portion by printing such as screen printing, it is possible to accurately form a design of the first layer.

For example, in the case of forming the first layer on the stepped portion by screen printing, the printing may not be performed depending on the rear surface shape of the transparent resin layer. That is, in the screen printing, since ink is pushed out from a screen mesh and is printed, the screen mesh need to be parallel to the rear surface of the transparent resin layer. When there is a protruding part which largely protrudes on the rear surface, since the protruding part causes flow mark or weld to the transparent resin layer at the time of molding, no design is established.

In contrast, when the laser is used, it is possible to reliably separate the excess part of the first layer regardless of the rear surface shape of the transparent resin layer.

In the present teachings, the general portion and the stepped portion of the rear surface of the transparent resin layer may be a concave portion or a convex portion. The first layer is formed on the stepped portion.

The decorative member of the present teachings is manufactured by the aforementioned decorative member manufacturing method, so that it is possible to view a design accurately formed on the uneven surface of the transparent resin layer.

Since the inclination angle and the width of the inclination portion are in the aforementioned range, it is possible to three-dimensionally view the first layer with a good appearance.

The present teachings will become more fully understood from the detailed description given hereinbelow and the accompanying drawing which is given by way of illustration only, and thus is not limitative of the present teachings and wherein:.

A decorative member and a manufacturing method thereof according to a first embodiment will be described with reference to each of drawings.

As illustrated in <FIG>, a decorative member <NUM> according to the present embodiment is a millimeter wave transmission cover attached to the center of a front grill <NUM> of a vehicle. The decorative member <NUM> is provided at a rear surface side thereof with a millimeter wave oscillation receiver (not illustrated).

As illustrated in <FIG>, the decorative member <NUM> is a thin plate and thicknesses of its all parts are set to be n times of <NUM>/<NUM> of a wavelength of a millimeter wave. In the decorative member <NUM>, the center is gently curved to protrude to a surface 1a side. The decorative member <NUM> has a transparent resin layer <NUM>, a base layer <NUM>, and a decorative layer <NUM> interposed between the transparent resin layer <NUM> and the base layer <NUM>. The transparent resin layer <NUM> is made of a transparent resin material, and for example, PC (polycarbonate) is used.

A surface 2a of the transparent resin layer <NUM> is a smooth surface. A rear surface 2b of the transparent resin layer <NUM> has an outer peripheral part <NUM> and an inner part <NUM> positioned at an inner side from the outer peripheral part <NUM> and recessed with respect to the outer peripheral part <NUM>. A depth T of the inner part <NUM> from the outer peripheral part <NUM> is <NUM>.

The outer peripheral part <NUM> has a flat shape. The outer peripheral part <NUM> is covered by a black translucent outer peripheral print part <NUM>.

As illustrated in <FIG>, the inner part <NUM> has a general portion <NUM>, a stepped portion <NUM> recessed with respect to the general portion <NUM>, and an inclination portion <NUM> provided between the general portion <NUM> and the stepped portion <NUM>. A height difference H between the stepped portion <NUM> and the general portion <NUM> of the rear surface 2b of the transparent resin layer <NUM>, that is, a height of the inclination portion <NUM> is equal to or more than <NUM> and is equal to or less than <NUM>. In the present embodiment, the height difference H between the stepped portion <NUM> and the general portion <NUM> of the rear surface 2b of the transparent resin layer <NUM> is <NUM>.

As illustrated in <FIG>, the inclination portion <NUM> is interposed between the general portion <NUM> and the stepped portion <NUM>. An inclination angle α of the inclination portion <NUM> with respect to a normal line D of the general portion <NUM> is <NUM>°. An upper end 26a of the inclination portion <NUM> is a part connected to the general portion <NUM>, and a lower end 26b of the inclination portion <NUM> is a part connected to the recessed stepped portion <NUM>. R1 and R2 of the upper end 26a and the lower end 26b of the inclination portion <NUM> are all chamfered in an arc shape having a curvature radius of <NUM>. A width W from the upper end 26a to the lower end 26b of the inclination portion <NUM> when the inclination portion <NUM> has been projected along the normal line of the rear surface 2b of the transparent resin layer <NUM> is <NUM>.

As illustrated in <FIG>, the decorative layer <NUM> is provided to the rear surface 2b side of the transparent resin layer <NUM>, and has a first layer <NUM> and a second layer <NUM> sequentially arranged from the rear surface 2b side. The first layer <NUM> includes a metal layer having a radio wave transmission characteristic. As the metal layer, an indium layer is preferable. The indium layer may have a sea-island structure in which indium exists insularly in various places from the standpoint of a radio wave transmission characteristic. The second layer <NUM> is a black coating layer. The first layer <NUM> has a thickness of about <NUM> to <NUM> and the second layer <NUM> has a thickness of about <NUM> to <NUM>.

The first layer <NUM> covers the recessed stepped portion <NUM> of the rear surface 2b of the transparent resin layer <NUM>. The second layer <NUM> covers the entire of the rear surface 2b of the transparent resin layer <NUM>. The first layer <NUM> including the indium is positioned at the recessed stepped portion <NUM> and is positioned near the surface 1a of the decorative member <NUM> as compared with the second layer <NUM> including the black coating layer. As illustrated in <FIG>, when the decorative member <NUM> is viewed from the surface 1a side, a black character of the black coating layer is viewed in the brightly colored area of the indium. The brightly colored figure floats up to a front side from the black area and is three-dimensionally viewed.

The base layer <NUM> is made of a colored resin material, for example, AES (acrylonitrile ethylene styrene copolymer).

A manufacturing method of the decorative member <NUM> of the present embodiment will be described using a flowchart of <FIG>.

In step S10 (preparation step), polycarbonate resin is injection-molded using a mold, so that the transparent resin layer <NUM> is obtained.

In step S20 (surface hard coat step), a hard coat process is performed for the surface 2a of the transparent resin layer <NUM>.

In step S30 (rear surface printing step), as illustrated in <FIG>, blank ink is printed on the outer peripheral part <NUM> of the rear surface 2b of the transparent resin layer <NUM> by a screen printing method and the like, so that the black translucent outer peripheral print part <NUM> is formed on the outer peripheral part <NUM>.

In step S40 (first layer disposing step), as illustrated in <FIG>, the first layer <NUM> including indium is formed on the entire of the inner part <NUM> of the rear surface 2b of the transparent resin layer <NUM> by a sputtering method. The first layer <NUM> may be formed by a deposition method.

In step S50 (separation step), as illustrated in <FIG>, the transparent resin layer <NUM> is fixed to a jig such that the rear surface 2b of the transparent resin layer <NUM> is upward. In the first layer <NUM> on the rear surface 2b of the transparent resin layer <NUM>, laser is irradiated to an excess part B, other than a part A covering the stepped portion <NUM>, so that the excess part B is separated. As the laser irradiation device, MDV9920 (product name) manufactured by keyence Corporation has been used. The laser irradiation energy per unit area is <NUM> mJ. In the laser irradiation conditions, a laser spot diameter is <NUM>, a laser spot pitch is <NUM>, a laser frequency is <NUM>, and a laser wavelength is <NUM>. It is sufficient if laser transmittance is <NUM>% to <NUM>%, and it is preferable that a laser movement speed is <NUM>/sec to <NUM>/sec. In this case, there is no discoloration due to laser burning of the transparent resin layer <NUM> and residue of the indium, which is the first layer <NUM>, is also not seen.

The boundary between the irradiation area and the non-irradiation area of the laser is set as a center 26c in the width direction of the inclination portion <NUM>. The excess part B separated by the laser is an area from the general portion <NUM> and the upper end 26a of the inclination portion <NUM> to the center 26c in terms of design. When measuring a molding error range of the transparent resin layer <NUM>, a positional shift range of a fixing jig for laser irradiation, and a variation range of a laser irradiation position, they are sequentially ± <NUM>, ± <NUM>, and ± <NUM>. Their total error is ± <NUM>, and is separation tolerance by which a separation position may be shifted with respect to the transparent resin layer <NUM>. On the other hand, as illustrated in <FIG> and <FIG>, the width W of the inclination portion <NUM> is <NUM> and the inclination portion <NUM> exists in an area of ± <NUM> from the center 26c of the inclination portion <NUM>. Since the shift range of the laser irradiation position with respect to the transparent resin layer <NUM> is ± <NUM>, the laser enters into the width (± <NUM>) from the center 26c of the inclination portion <NUM>. Therefore, when the excess part B of the first layer <NUM> is separated by the laser irradiation, a boundary line L between the first layer <NUM> and the separation part is positioned on the inclination portion <NUM>. The first layer <NUM> does not almost remain in the upper end 26a side of the inclination portion <NUM> and mainly remains in the lower end 26b as compared with the upper end 26a side. The boundary line L between the first layer <NUM> and the separation part is positioned in the center 26c of the inclination portion <NUM> in many cases.

In step S60 (second layer disposing step), as illustrated in <FIG>, the second layer <NUM> is formed on the inner part <NUM> of the rear surface 2b side of the transparent resin layer <NUM> by coating using a black paint. The second layer <NUM> is an opaque black layer. The black paint has been obtained by mixing coloring with a resin material. For example, the coloring is carbon black and the resin material is acryl resin; however, the present teachings are not limited thereto.

In step S70 (base layer formation step), the transparent resin layer <NUM> is inserted into the mold and colored AES is injection-molded at the rear surface 2b side of the transparent resin layer <NUM>, so that the base layer <NUM> is formed on the entire of the rear surface 2b side.

As above, the decorative member <NUM> of the present embodiment is obtained.

According to the manufacturing method of the decorative member <NUM> of the present embodiment, the first layer <NUM> is disposed on the entire of the rear surface 2b of the transparent resin layer <NUM>, the part A covering the stepped portion <NUM> in the first layer <NUM> is allowed to remain, and the excess part B, other than the part A, is separated by laser irradiation. Therefore, it is possible to accurately separate the excess part B. When the first layer <NUM> is viewed from the surface 2a of the transparent resin layer <NUM>, it is possible to view an accurate design.

The inclination angle α of the inclination portion <NUM> with respect to the normal line D of the general portion <NUM> is <NUM>° to <NUM>° and the width W of the inclination portion <NUM> is large beyond <NUM> and is equal to or less than <NUM>. In the present embodiment, the inclination angle α of the inclination portion <NUM> with respect to the normal line D of the general portion <NUM> is <NUM>°, and the width W of the inclination portion <NUM> is <NUM>.

The width W of the inclination portion <NUM> is larger than the range <NUM> of the separation tolerance (± <NUM>). When laser is irradiated aiming at the center 26c of the inclination portion <NUM>, even though a laser irradiation positional shift occurs at the upper end 26a side or the lower end 26b side from the center 26c, the inclination portion <NUM> absorbs the shift, so that it is possible to allow the boundary line L between the first layer <NUM> and the separation part, from which the excess part B has been separated, to be positioned on the inclination portion <NUM>. Since the shift of the boundary line L between the first layer <NUM> and the separation part is positioned on the inclination portion <NUM>, the boundary line L is prevented from being shifted on the general portion <NUM> or the stepped portion <NUM>. When the first layer <NUM> is viewed from the surface 2a of the transparent resin layer <NUM>, since the first layer <NUM> is viewed as if it covers only the stepped portion <NUM>, it is possible to three-dimensionally view the first layer <NUM> with a good appearance.

When the inclination angle α is smaller than <NUM>°, even though a molding dimensional error of the transparent resin layer <NUM> or a laser irradiation positional shift at the time of installation of a laser irradiation jig occurs, the inclination portion <NUM> may not absorb the shift, or the boundary line L between the first layer <NUM> and the separation part may be positioned on the general portion <NUM> or the stepped portion <NUM>. When the inclination angle α exceeds <NUM>°, if it is viewed from the surface 1a side of the decorative member <NUM>, the inclination portion <NUM> is viewed. The boundary line L on the inclination portion <NUM> is apparently viewed and the contour of the first layer <NUM> appears to protrude as compared with the contour of the stepped portion <NUM>, so that the appearance of the first layer <NUM> may be reduced.

In the separation step, the separation of the excess part B of the first layer <NUM> is performed by the laser irradiation. Since the laser has a high degree of accuracy of an irradiation position, it is possible to accurately separate the excess part B of the first layer <NUM>. Therefore, according to the separation step of the present embodiment, as compared with the case in which the first layer <NUM> has been formed on the stepped portion <NUM> by printing such as screen printing, it is possible to accurately form a design of the first layer <NUM>.

For example, when the first layer <NUM> is formed on the stepped portion <NUM> by screen printing, the printing may not be performed depending on the rear surface shape of the transparent resin layer <NUM>. That is, in the screen printing, since ink is pushed out from a screen mesh and is printed, the screen mesh need to be parallel to the rear surface 2b of the transparent resin layer <NUM>. When there is a protruding part which largely protrudes on the rear surface 2b, since the protruding part causes flow mark or weld to the transparent resin layer <NUM> at the time of molding, no design is established.

In contrast, when the laser is used, it is possible to reliably separate the excess part B of the first layer <NUM> regardless of the rear surface shape of the transparent resin layer <NUM>, so that the first layer <NUM> can remain on the stepped portion <NUM>.

The decorative member <NUM> of the present embodiment is manufactured by the aforementioned decorative member manufacturing method, so that it is possible to view a design accurately formed on the uneven surface of the transparent resin layer <NUM>.

When the rear surface 2b of the transparent resin layer <NUM> after laser irradiation is observed by SEM (scanning electronic microscope), a sea-island structure is recognized in which indium exists insularly in many places of the part A of the first layer <NUM> subjected to no laser irradiation. The first layer <NUM> has not been observed in the separation part. In the inclination portion <NUM>, the boundary line L between the part A of the first layer <NUM> and the separation part is arranged. When the decorative member <NUM> is viewed from the surface 1a side, since the first layer <NUM> is viewed as if it covers only the stepped portion <NUM>, it is possible to three-dimensionally view the first layer <NUM> with a good appearance. Around the boundary line L of the part A, the sea-island structure of the indium remains. Around the boundary line L of the part A, residues of PC (components of the transparent resin layer) having a size of about <NUM> have been observed. Since the thickness of the second layer <NUM> is <NUM>, the residues of about <NUM> do not affect external appearance, an adhesion property, and millimeter wave attenuation.

In the transparent resin layer, when measuring optical attenuation of the separation part, from which the first layer has been separated by laser irradiation, and optical attenuation of the transparent resin layer before the first layer is formed, both are low with the same degree.

The color of the transparent resin layer (a resin layer before being processed) before the first layer is formed and the color of the transparent resin layer (a resin layer after separation) after laser separation have been measured with an L*a*b* display system. The laser irradiation conditions are similar to the aforementioned conditions of the present embodiment. From the measured values of the color of the resin layer before being processed and the color of the resin layer after separation, a color difference ΔE of the resin layer after separation from the resin layer before being processed has been obtained. When the color difference ΔE is smaller than <NUM>, it can be understood that it is not possible to recognize the color difference of the two. These results are illustrated in Table <NUM> below.

The color difference ΔE from the resin layer before being processed and the resin layer after separation is <NUM>. From this fact, it can be understood that laser is irradiated to the first layer, so that it is possible to separate the first layer from the rear surface of the transparent resin layer to the extent that the first layer is not recognizable.

A decorative member <NUM> of the present embodiment is different from the first embodiment in that a pattern layer <NUM> is coated on the outer peripheral part <NUM> of the rear surface 2b of the transparent resin layer <NUM> as illustrated in <FIG> and <FIG>.

In order to manufacture the decorative member <NUM> of the present embodiment, steps S10, S20, S30, and S40 have been performed as illustrated in <FIG>, similarly to the first embodiment. On the rear surface 2b of the transparent resin layer <NUM> after step S40, the first layer <NUM> is formed on the entire of the inner part <NUM> (see <FIG>).

After step S40 (first layer disposing step), step S45 (a partial coating step) is performed. In step S45, the pattern layer <NUM> is coated on a part of the outer peripheral part <NUM> of the rear surface 2b of the transparent resin layer <NUM> or the entire of the inner part <NUM> as illustrated in <FIG>. In order to form the pattern layer <NUM>, in the state in which a part of the outer peripheral part <NUM>, other than a pattern layer formation part, is covered with a mask <NUM>, the rear surface 2b of the transparent resin layer <NUM> is coated, and then the mask <NUM> is removed. For the pattern layer <NUM>, an opaque colored paint of a brown and the like has been used.

In step S50 (separation step), as illustrated in <FIG>, in the first layer <NUM> and the pattern layer <NUM> on the rear surface 2b of the transparent resin layer <NUM>, laser is irradiated to an excess part B, other than the part A covering the stepped portion <NUM>, so that the excess part B is separated. The laser irradiation conditions are similar to those of the first embodiment except that the irradiation energy per unit area is <NUM> mJ. The width W of the inclination portion <NUM> of the rear surface 2b of the transparent resin layer <NUM> is <NUM> and the inclination angle α of the inclination portion <NUM> is <NUM>°. The width W and the inclination angle α are similar to those of the first embodiment. Since the width W is larger than separation tolerance (± <NUM>) due to the difference of laser irradiation as described in the first embodiment, even though positional shift of laser irradiation occurs, the boundary line L between the first layer <NUM> and the pattern layer <NUM> remaining after the separation and the separation part thereof is positioned on the inclination portion <NUM>.

In step S60 (second layer disposing step), as illustrated in <FIG>, a black coating layer is disposed at the rear surface 2b side of the transparent resin layer <NUM> as the second layer <NUM>.

In step S70 (base layer formation step), as illustrated in <FIG>, the rear surface 2b of the transparent resin layer <NUM>, on which the second layer <NUM> has been formed, is covered with the base layer <NUM>. The formation of the base layer <NUM> has been performed similarly to the first embodiment.

As above, the decorative member <NUM> of the present embodiment has been obtained.

When the obtained decorative member <NUM> is viewed from the surface, the pattern layer <NUM> is recognized at the outer peripheral part <NUM> through a transparent black outer peripheral print part <NUM>. At the inner part <NUM>, the pattern layer <NUM> is conceal to the rear surface side of the first layer <NUM> and is not seen. At the inner part <NUM>, the bright color of the indium of the first layer <NUM> stands out on a front side and is three-dimensionally recognized in the black area of the second layer <NUM> similarly to the first embodiment.

A decorative member <NUM> of the present embodiment is different from the first embodiment in that a first layer <NUM> of the decorative layer <NUM> is a black coating layer and a second layer <NUM> is an indium layer as illustrated in <FIG>.

The first layer <NUM> is formed on a stepped portion <NUM> protrudingly provided in the inner part <NUM> of the rear surface 2b of the transparent resin layer <NUM>. On the rear surface 2b of the transparent resin layer <NUM>, the second layer <NUM>, which is the indium layer, is formed on the entire of the inner part <NUM>, including the first layer <NUM>.

In order to manufacture the decorative member <NUM> of the present embodiment, steps S10, S20, and S30 have been performed (see <FIG>), similarly to the first embodiment. On the rear surface 2b of the transparent resin layer <NUM> after step S30, a black translucent outer peripheral print part <NUM> is formed on the outer peripheral part <NUM> (see <FIG>).

In step S40 (first layer disposing step), as illustrated in <FIG>, a screen mesh <NUM> is arranged at the rear surface 2b side of the transparent resin layer <NUM>. In the screen mesh <NUM>, holes <NUM> are opened in parts corresponding to the stepped portion <NUM> and an inclination portion <NUM>. As illustrated in <FIG>, black ink is pushed out from the holes <NUM> of the screen mesh <NUM>, so that the first layer <NUM> is formed on the stepped portion <NUM> and the inclination portion <NUM>. In the screen printing using the screen mesh <NUM>, since printing position accuracy is lower than that of laser, the first layer <NUM> is formed on the inclination portion <NUM> as well as the stepped portion <NUM> by the screen printing, and the first layer <NUM> on the inclination portion <NUM> is separated by laser in a subsequent separation step. The black ink used in the screen printing is similar to the black ink in step S60 (second layer disposing step) in the first embodiment.

In step S50 (separation step), as illustrated in <FIG>, laser is irradiated to an excess part B of the first layer <NUM>, so that the excess part B is separated. In this way, the first layer <NUM> remains on the stepped portion <NUM> of the rear surface 2b of the transparent resin layer <NUM>.

In the present embodiment, laser is set to be irradiated to an area from a general portion <NUM> to a center 260c of the inclination portion <NUM>. The excess part B separated by the laser is an area from a lower end 260b to the center 260c of the inclination portion <NUM> in the first layer <NUM> in terms of design. Similarly to the first embodiment, separation tolerance is ± <NUM>. The separation tolerance is smaller than the width W (± <NUM>) from the center 260c of the inclination portion <NUM>. Therefore, also in the present embodiment, when the excess part B of the first layer <NUM> is separated by laser irradiation, the boundary line L between the first layer <NUM> and the separation part is positioned on the inclination portion <NUM>.

In step S60 (second layer disposing step), as illustrated in <FIG>, the indium layer as the second layer <NUM> is disposed on the entire of the inner part <NUM>. The indium layer can be disposed by a sputtering method or a deposition method.

Thereafter, step S70 (base layer formation step) is performed similarly to the first embodiment, so that the decorative member <NUM> of the present embodiment is obtained.

When the decorative member <NUM> of the present embodiment is viewed from the surface 1a side, the bright color part of the second layer <NUM> formed on the general portion <NUM> and including indium floats up and is three-dimensionally and clearly seen during black coating.

In step S40 (first layer disposing step), the first layer <NUM> is formed as a coating layer by using the screen mesh <NUM>. When positional shift occurs in the screen mesh <NUM>, the first layer <NUM> causes positional shift. However, since the first layer <NUM> is accurately trimmed by laser in step S50 (separation step), it is possible to form the first layer <NUM> at an accurate position.

The first layer <NUM> is formed in advance on the stepped portion <NUM> and the inclination portion <NUM> around the stepped portion <NUM> by the screen printing, and a part of the first layer <NUM> covering the stepped portion <NUM> is separated by laser afterward. Therefore, an area of a laser separation area becomes small. It is possible to shorten a laser separation time.

The decorative member <NUM> of the aforementioned embodiment is a radio wave transmission cover for millimeter waves, but can also be used in a radio wave transmission cover for other electric waves. The decorative member <NUM> of the aforementioned embodiment can also be used as emblems for decoration. These emblems are not limited to vehicles, and can be used in all scenes.

According to the aforementioned configuration, the first layers <NUM> and <NUM> are disposed on at least the concave or convex stepped portions <NUM> and <NUM> and the inclination portions <NUM> and <NUM> in the rear surface 2b of the transparent resin layer <NUM>, and the parts A covering the stepped portions <NUM> and <NUM> in the first layers <NUM> and <NUM> are allowed to remain, and the excess parts B, other than the parts A, are separated by the laser irradiation. Therefore, it is possible to accurately separate the excess parts B. When the first layers <NUM> and <NUM> are viewed from the surface 2a of the transparent resin layer <NUM>, it is possible to view an accurate design.

The inclination angles α of the inclination portions <NUM> and <NUM> with respect to the normal lines D of the general portions <NUM> and <NUM> are <NUM>° to <NUM>° and the widths W of the inclination portions <NUM> and <NUM> are large beyond <NUM> and are equal to or less than <NUM>. The widths W of the inclination portions <NUM> and <NUM> are larger than separation tolerance when the first layers <NUM> and <NUM> are separated by the laser irradiation. Therefore, even though a molding dimensional error or a positional shift at the time of installation of a laser irradiation jig occurs in the transparent resin layer <NUM>, these errors are absorbed, so that the boundary lines L between the first layers <NUM> and <NUM> and the separation parts, from which the excess parts B have been separated, can be positioned on the inclination portions <NUM> and <NUM>. The boundary lines L between the first layers <NUM> and <NUM> and the separation parts are allowed to be positioned on the inclination portions <NUM> and <NUM>, so that the boundary lines L are prevented from being shifted on the general portions <NUM> and <NUM> or the stepped portions <NUM> and <NUM>.

Since the inclination angles α of the inclination portions <NUM> and <NUM> are <NUM>° to <NUM>°, when the first layers <NUM> and <NUM> are viewed from the surface side of the transparent resin layer, the first layers <NUM> and <NUM> remaining on the inclination portions <NUM> and <NUM> are difficult to be viewed. The first layer <NUM> is viewed as if it covers only the stepped portion <NUM>, so that it is possible to three-dimensionally view the first layer <NUM> with a good appearance.

In the separation step, the separation of the excess parts B of the first layers <NUM> and <NUM> is performed by the laser irradiation. Since the laser has a high degree of accuracy of an irradiation position, it is possible to accurately separate the excess parts B of the first layers <NUM> and <NUM>. Therefore, according to the separation step of the aforementioned embodiment, as compared with the case in which the first layers <NUM> and <NUM> are formed on the stepped portions <NUM> and <NUM> by printing such as screen printing, it is possible to accurately form designs of the first layers <NUM> and <NUM>.

For example, in the case of forming the first layers <NUM> and <NUM> by the screen printing, the printing may not be performed depending on the rear surface shape of the transparent resin layer <NUM>. That is, in the screen printing, since ink is pushed out from a screen mesh and is printed, the screen mesh need to be parallel to the rear surface 2b of the transparent resin layer <NUM>. When there is a protruding part which largely protrudes on the rear surface 2b, since the protruding part causes flow mark or weld to the transparent resin layer <NUM> at the time of molding, no design is established.

In contrast, when the laser is used, it is possible to reliably separate the excess parts B of the first layers <NUM> and <NUM> regardless of the shape of the rear surface 2b of the transparent resin layer <NUM>, so that it is possible to form designs of the first layers <NUM> and <NUM>.

In the aforementioned embodiment, the general portions <NUM> and <NUM> and the stepped portions <NUM> and <NUM> of the rear surface 2b of the transparent resin layer <NUM> may be concave portions or convex portions. In the separation step, the first layers <NUM> and <NUM> remain on the stepped portions <NUM> and <NUM>.

the inclination angles α of the inclination portions <NUM> and <NUM> with respect to the normal lines D of the general portions <NUM> and <NUM> being <NUM>° to <NUM>°, the widths W of the inclination portions <NUM> and <NUM> are large beyond <NUM> and are equal to or less than <NUM>, and the decorative layer <NUM> has the first layers <NUM> and <NUM> that cover the stepped portions <NUM> and <NUM> of the rear surface 2b of the transparent resin layer <NUM>, and the second layers <NUM> and <NUM> that cover parts of the rear surface 2b of the transparent resin layer <NUM>, which are not covered by at least the first layers <NUM> and <NUM>.

The decorative member <NUM> of the present embodiment is manufactured by the aforementioned manufacturing method of the decorative member <NUM>, so that it is possible to view a design accurately formed on the uneven surface of the transparent resin layer <NUM>.

Since the inclination angle α and the width W of the inclination portion <NUM> are in the aforementioned range, it is possible to three-dimensionally view the first layers <NUM> and <NUM> with a good appearance.

In addition, it is sufficient if a decorative member has the following aspects.

Claim 1:
A radio wave transmission cover for a vehicle comprising:
a transparent resin layer (<NUM>) provided on a rear surface thereof with a general portion (<NUM>), a stepped portion (<NUM>) recessed or protrudingly provided with respect to the general portion, and an inclination portion provided between the stepped portion and the general portion; and
a decorative layer (<NUM>) provided on the rear surface of the transparent resin layer, wherein the decorative layer includes: a first layer (<NUM>) that covers the stepped portion of the rear surface of the transparent resin layer; and a second layer (<NUM>) that covers a part of the rear surface of the transparent resin layer, which is not covered by at least the first layer,
characterized in that
an inclination angle of the inclination portion with respect to a normal line of the general portion is equal to or more than <NUM>° and is equal to or less than <NUM>°;
a width of the inclination portion is large beyond <NUM> and is equal to or less than <NUM>;
in the stepped portion of the rear surface of the transparent resin layer, a height difference with the general portion is equal to or more than <NUM> and is equal to or less than <NUM>,
the first layer (<NUM>) that covers the stepped portion is provided by
disposing a first layer (<NUM>) on at least the stepped portion and the inclination portion of the rear surface of the transparent resin layer, and
separating an excess part, other than a part covering the stepped portion, in the first layer by laser irradiation, wherein the part covering the stepped portion in the first layer remains, and
the width of the inclination portion is larger than a separation tolerance when the first layer (<NUM>) is separated by laser irradiation such that a boundary line between a part covered with the first layer on the rear surface of the transparent resin layer and a part not covered with the first layer is positioned on the inclination portion.