JP7290220B2 - Lighting device and manufacturing method thereof - Google Patents

Description

TECHNICAL FIELD The present invention relates to an illumination device including a design plate and light irradiation means. The present invention also relates to a method for manufacturing the lighting device.

2. Description of the Related Art Conventionally, lighting devices have been used mainly for the purpose of illuminating a room or the like, but in recent years, they have come to be used as decorations for vehicles, buildings, and the like.

Patent Literature 1 describes an automotive interior lighting device comprising a light diffusing plate installed in the interior of an automobile and having a decorative design layer on its surface, and a light source installed on the back side of the light diffusing plate. It is This automotive interior lighting device has a metallic appearance when it is turned off (daytime), but when it is turned on (nighttime), the light diffuses and the light floats vaguely. be. By using this lighting device, it is possible to achieve different presentations in the daytime and at night.

In recent years, with the diversification of consumer needs, there is a demand for a lighting device that has a high level of designability both when it is turned off and when it is turned on. However, it is difficult to say that the lighting device described in Patent Document 1 fully satisfies such requirements.

JP 2009-18747 A

SUMMARY OF THE INVENTION It is an object of the present invention to provide a lighting device having a deep three-dimensional pattern when turned off and a shading pattern when turned on, and the manufacture thereof. be.

The above issues are
A lighting device comprising a design plate formed by laminating a back plate and a front plate, and light irradiation means;
The back plate is made of a resin composition containing a metallic pigment or a pearl pigment, and has unevenness on one surface thereof,
One surface of the front plate is in contact with the unevenness and the other surface is flat,
The back plate is arranged in a direction facing the light irradiation means,
The resin constituting the front plate has a total light transmittance (X) of 20 to 100%/2 mm, and the resin constituting the back plate has a total light transmittance (Y) of 0.1 to 80%/2 mm. is solved by providing a lighting device characterized by:

At this time, the maximum thickness (A) of the back plate is 1 to 20 mm, the minimum thickness (B) is 0.5 to 10 mm, and the difference between the thickness (A) and the thickness (B) is 0.5 mm. It is preferably 5 mm or more. It is also preferable that the pitch of the unevenness is 0.5 to 20 mm. It is also preferable that the thickness of the back plate gradually changes. It is also preferable that the design plate has a thickness of 2 to 30 mm. It is also preferable that the front plate is made of a resin having a haze of 90% or less.

Moreover, it is preferable that the light irradiation means irradiate diffused light. It is also preferable that the light irradiation means has a light diffusion plate and a light source. It is also preferable that a light shielding pattern is formed between the back plate and the light irradiation means. It is also preferable that the light irradiation means includes pattern information.

The above issues are
A method for manufacturing the above lighting device;
Step 1 of forming the back plate by injecting and filling a resin composition containing a metallic pigment or a pearl pigment into a cavity for the back plate formed between the common mold and the first replacement mold;
Step 2 of exchanging the first exchange mold for a second exchange mold;
a step 3 of injecting and filling a resin into a front plate cavity formed between the back plate and the second replacement mold to form the front plate;
a step 4 of cooling the common mold and the second replacement mold and removing the design plate from the common mold and the second replacement mold;
The problem can also be solved by providing a method of manufacturing a lighting device, which has a step 5 of arranging the design plate so that the back plate faces the light irradiation means.

A preferred embodiment of the present invention is an automotive interior component comprising the lighting device described above.

The lighting device of the present invention has a deep three-dimensional pattern when turned off, and a shading pattern when turned on. Further, according to the manufacturing method of the present invention, such a lighting device can be manufactured easily.

FIG. 4 is a diagram showing the shape of a design plate produced in Examples. FIG. 2 is a diagram showing a schematic cross-sectional view taken along line AA of FIG. 1; 3 is an enlarged view of a portion (B) surrounded by a square in the AA line cross-sectional view of FIG. 2; FIG. 10 is an appearance photograph when lighting is turned off in Example 4. FIG. 10 is an appearance photograph when lighting is turned on in Example 4. FIG. FIG. 11 is an appearance photograph when lighting is turned off in Example 6. FIG. 11 is an appearance photograph when lighting is turned on in Example 6. FIG. 13 is an appearance photograph when lighting is turned off in Example 13. FIG. FIG. 13 is an appearance photograph when lighting is turned on in Example 13. FIG. 4 is an appearance photograph when lighting is turned off in Comparative Example 1. FIG. 4 is an appearance photograph when lighting is turned on in Comparative Example 1. FIG. 10 is an appearance photograph when lighting is turned off in Comparative Example 3. FIG. 10 is an appearance photograph when lighting is turned on in Comparative Example 3. FIG.

TECHNICAL FIELD The present invention relates to an illumination device including a design plate and light irradiation means. Hereinafter, the lighting device of the present invention will be described with reference to the drawings.

In order to obtain a lighting device that has a deep three-dimensional pattern when turned off and a shading pattern when turned on, the present inventors made a resin composition containing a metallic pigment, and provided an uneven surface on one surface of the resin composition. (Comparative Example 1). When the appearance when turned off was evaluated, compared to the case where the metallic pigment was not used (Comparative Example 2), the light reflectance on the uneven surface was improved, resulting in a more three-dimensional pattern. Since the reflected light enters the eyes directly, a deep three-dimensional effect cannot be obtained.

As a result of intensive studies by the present inventors, it was possible to obtain a lighting device having a deep three-dimensional pattern when turned off by laminating a front panel on such a back panel. In addition, it was possible to express a light and shade pattern when lit, and it was also possible to express patterns with different impressions when lit and when lit. On the other hand, even in the case of the design plate in which the back plate and the front plate are laminated, when the metallic pigment was not mixed in the back plate (Comparative Example 3), the three-dimensional effect of the pattern when the light was turned off was not felt. , Only a slight gradation pattern could be confirmed when lit.

FIG. 1 is a schematic diagram showing an example of a design plate according to the present invention. 2 is a schematic cross-sectional view taken along line AA of FIG. 1, and FIG. 3 is an enlarged view of a portion (B) surrounded by a square in the schematic cross-sectional view along line AA of FIG. The unit of distance shown in the figure is mm.

First, the back plate of the design plate will be described. The back plate is made of a resin composition containing a metallic pigment or a pearl pigment, and has unevenness on one surface thereof.

The resin composition used in the present invention can be obtained by adding a metallic pigment or pearlescent pigment to the resin that forms the back plate. The type of metallic pigment is not particularly limited, and examples include those containing flakes of metals such as aluminum, gold, silver, and copper. The type of pearl pigment is not particularly limited, and examples include those containing mica and the like. Among them, metallic pigments are more suitable for expressing clear unevenness. Moreover, a colored pigment or dye can also be contained together. In the present invention, a resin composition containing a metallic pigment or pearl pigment can be obtained by using a masterbatch in which these metallic pigments or pearl pigments are dispersed in a resin. The content of the metallic pigment or pearl pigment is not particularly limited, and can be appropriately selected within a range that does not hinder the effects of the present invention.

The back plate used in the present invention has unevenness on one surface thereof. The shape of the unevenness is not particularly limited. For example, rounded wavy irregularities, rectangular irregularities, triangular peaks, and the like as shown in FIGS.

It is preferable that the pitch of the unevenness is 0.5 to 20 mm. Here, the pitch of the unevenness means the distance from one recessed portion to the adjacent recessed portion or the distance from one projected portion to the adjacent projected portion. If the pitch of the unevenness is out of the above range, the pattern may have insufficient three-dimensional effect. The pitch of the unevenness is more preferably 1 mm or more, more preferably 2 mm or more. On the other hand, it is more preferable that the pitch of the unevenness is 15 mm or less. It should be noted that all the unevenness does not need to have the same pitch, and as shown in FIG. I don't mind.

Preferably, the surface of the back plate further has a line pattern (not shown), and the pitch of the line pattern is smaller than the pitch of the unevenness. As a result, metallic welds become less noticeable. Although the direction of the streak pattern is not particularly limited, it is preferably along the grooves of the unevenness. The stripe pattern may be a stripe pattern that is regularly formed at regular intervals, or may be a random stripe pattern. Although the width of the stripes of the stripe pattern is not limited, it is preferably 0.1 to 2 mm. It is preferable that the ratio (P ₁ /P 2 ) of the pitch ( _{P 1} ) of the unevenness and the width (P ₂ ) of the striped pattern is 3 or more. (P ₁ /P ₂ ) is usually 20 or less. Incidentally, in Examples described later, about 5 to 8 streak patterns are confirmed in the grooves of the unevenness with a pitch of about 5 to 8 mm.

It is preferable that the back plate has a maximum thickness (A) of 1 to 20 mm and a minimum thickness (B) of 0.5 to 10 mm. By setting the maximum thickness (A) and the minimum thickness (B) within the above ranges, it is possible to maintain the strength of the design board while suppressing increases in the weight and manufacturing cost of the design board. More preferably, the maximum thickness (A) is 2 mm or more. More preferably, the maximum thickness (A) is 10 mm or less. On the other hand, it is more preferable that the minimum thickness (B) is 1 mm or more. More preferably, the minimum thickness (B) is 5 mm or less.

It is preferable that the difference between the thickness (A) and the thickness (B) is 0.5 mm or more. If the difference between the thickness (A) and the thickness (B) is less than 0.5 mm, the three-dimensional effect of the pattern may be insufficient. More preferably, the difference between the thickness (A) and the thickness (B) is 1 mm or more. The difference between thickness (A) and thickness (B) is usually 5 mm or less.

It is preferable that the thickness of the back plate gradually changes. Here, FIG. 2 shows an example in which the thickness gradually changes along the direction perpendicular to the uneven grooves. As shown in FIG. 2, when the design plate has a uniform thickness as a whole, the thickness of the front plate is thick at the portions where the thickness of the back plate is thin, and the thickness of the front plate is thin at the portions where the thickness of the back plate is thick. By setting the total light transmittance (X) of the front plate to a predetermined value or less, when the light is turned off, the color is shaded according to the change in the thickness of the back plate, and the three-dimensional pattern is produced according to the observation position. It becomes a lighting device with a high design effect that causes a change in feeling.

In the present invention, the total light transmittance (Y) of the resin forming the back plate is 0.1 to 80%/2 mm. If the total light transmittance (Y) is less than 0.1%/2 mm, the light from the light irradiating means will not sufficiently pass through the design plate, and the lighting device will not function satisfactorily. On the other hand, when the total light transmittance (Y) exceeds 80%/2 mm, it becomes difficult to display a shading pattern when lit.

Here, if a back plate having a high total light transmittance (Y) is used, a bright illumination device can be obtained when lit. Further, as will be described later, when the lighting device has a light shielding pattern formed between the back plate and the light irradiation means, or when the light irradiation means includes pattern information, the total light transmittance (Y) is When the height is increased, the light shielding pattern and pattern information can be clearly displayed. When emphasizing such a point, the total light transmittance (Y) is preferably 2%/2 mm or more, more preferably 4%/2 mm or more, and 10%/2 mm or more. More preferred.

On the other hand, when a back plate with a low total light transmittance (Y) and a high content of metallic pigments is used, the reflectance on the uneven surface of the back plate increases, so that a deeper three-dimensional pattern is displayed when the light is turned off. be able to. When emphasizing such a point, the total light transmittance (Y) is preferably 40%/2 mm or less, more preferably 20%/2 mm or less, and 10%/2 mm or less. More preferred. The total light transmittance (Y) is a value measured according to JIS K7361-1 (1997) and includes a decrease due to surface reflection (the same applies to the total light transmittance (X) below).

Next, the front plate used in the present invention will be explained. As shown in FIGS. 2 and 3, one surface of the front plate is in contact with the irregularities and the other surface is flat. Here, as long as the unevenness of the back plate can be visually recognized, the flat surface of the front plate may have embossments or scratches as long as the effects of the present invention are not hindered. Also, the surface of the back plate may have unevenness. Moreover, the uneven shape may be produced by using a mold, or may be produced by cutting the product.

In the present invention, the total light transmittance (X) of the resin forming the front plate is 20-100%/2 mm. If the total light transmittance (X) is less than 20%/2 mm, the light from the light irradiation means does not sufficiently pass through the design plate, making it difficult to function as a lighting device and making it difficult to visually recognize the pattern. . The total light transmittance (X) is preferably 30%/2 mm or more, more preferably 40%/2 mm or more.

On the other hand, by lowering the total light transmittance (X), when the light is turned off, the color changes depending on the thickness of the front plate, and the three-dimensional effect of the pattern changes depending on the viewing position. becomes higher. When such a design effect is desired, the total light transmittance (X) is preferably 90%/2 mm or less, more preferably 80%/2 mm or less.

Further, in the front panel, by increasing the haze, the concave-convex pattern can be made matte. In order to obtain such a design effect, the front plate is preferably made of a resin having a haze of 30% or more, more preferably 60% or more. If the haze is too high, the visibility of the uneven pattern may be impaired, so the front plate is preferably made of a resin with a haze of 90% or less, more preferably 70% or less.

The total light transmittance (Y), (X) and haze can be adjusted by adding pigments or dyes to the resin for the back plate and the resin for the front plate. At this time, the back plate and the front plate may be colored. In this way, by appropriately adjusting the total light transmittance (X) of the resin forming the front panel and the total light transmittance (Y) of the resin forming the back panel, the lighting device can be The design property can be changed according to the preference of the observer.

In the present invention, resins for the back plate and the front plate are not particularly limited, and examples thereof include polycarbonate resin, ABS resin and acrylic resin. Also, the resin may be a polymer blend. Furthermore, the resin may be colored or colorless.

Next, the lighting device of the present invention will be described. The illumination device of the present invention includes the above-described design plate and light irradiation means. In the illumination device of the present invention, the back side of the design plate is arranged in a direction facing the light irradiation means.

The type of the light irradiation means is not particularly limited, and for example, a point light source such as a light emitting diode (LED), a line light source such as a fluorescent lamp, or the like can be used.

In the present invention, it is preferable that the light irradiation means irradiate diffused light. By using the light irradiating means for irradiating diffused light, it is possible to express a dark and light pattern with depth at the time of lighting. As the light irradiation means for irradiating diffused light, a light irradiation means having a light diffusion plate and a light source is preferably used.

Further, it is preferable that a light shielding pattern is formed between the back plate and the light irradiation means. A method for forming the light shielding pattern is not particularly limited. Examples of the forming method include a method of forming a pattern on the surface of the back plate or the light irradiation surface of the light irradiation means by printing, a method of attaching a patterned film to these surfaces, painting, plating, vapor deposition, sputtering, and the like. and hot stamping. Also, the shape of the light-shielding pattern is not particularly limited, and examples thereof include letters and figures. As shown in a thirteenth embodiment, which will be described later, when the lighting device is turned on, characters that were not displayed when the lighting device was turned off are displayed on the surface of the design plate.

Moreover, it is also preferable that the light irradiation means includes pattern information. The pattern information is characters and patterns indicated by the light output from the light irradiation means. Display devices such as a liquid crystal display device, an organic EL (Electro Luminescence) display device, a plasma display device, and an LED display device can be used as light irradiation means including pattern information. More specifically, it is a display panel for a car navigation system, a display panel for electronic parts, an electrostatic switch for operation, and the like.

The manufacturing method of the lighting device of the present invention is not particularly limited, but a preferable manufacturing method is to add a resin composition containing a metallic pigment or a pearl pigment to the back plate cavity formed between the common mold and the first replacement mold. Step 1 of injecting and filling to form the back plate; Step 2 of replacing the first replacement mold with the second replacement mold; and a front plate cavity formed between the back plate and the second replacement mold. a step 3 of injecting and filling a resin into the mold to form the front panel; and a step 4 of cooling the common mold and the second replacement mold and removing the design plate from the common mold and the second replacement mold. 3. The method has a step 5 of arranging the design plate so that the back plate faces the light irradiating means.

In step 1, a resin composition containing a metallic pigment or pearl pigment is injected and filled into a cavity for the back surface formed between the common mold and the first replacement mold to form the back plate. By injecting resin into the cavity for the back surface, a primary molded body corresponding to the back plate of the design plate is formed. At this time, by using the first replacement mold having the uneven pattern or the striped pattern on the surface, the uneven pattern or the striped pattern is transferred to one surface of the back plate.

Molding conditions during injection molding are not particularly limited, but it is preferable to set the cylinder temperature to 180 to 330°C. Each of the common mold and the first exchange mold may be composed of a plurality of molds.

Then, after the resin is filled into the back surface cavity, clamped, compressed, and cooled, the first replacement mold is replaced with the second replacement mold in the subsequent step 2 .

In step 3, the front plate is formed by injecting and filling a resin into the front plate cavity formed between the rear plate and the second replacement mold. By injecting resin into the cavity for the front plate, a secondary molded body corresponding to the front plate of the design plate is formed on the primary molded body (back plate). Molding conditions during injection molding are not particularly limited, but it is preferable to set the cylinder temperature to 180 to 350°C.

Then, in step 4, the common mold and the second exchange mold are cooled, and the design plate is taken out from the common mold and the second exchange mold. A lighting device is obtained by arranging the design plate.

After step 4, a light shielding pattern can be formed on the surface of the back plate. A method for forming the light-shielding pattern is not particularly limited, and the above-described method can be used.

After step 4 or after step 5, the surface of the front plate may be subjected to surface treatment. For example, the surface of the front plate can be painted or plated. Examples of coating include spray coating, brush coating, electrodeposition coating, electrostatic coating, and ultraviolet curing coating. Plating includes electroplating, electroless plating, vapor deposition, and the like. A film can also be laminated on the surface of the front panel. Films used at this time include an anti-glare film (anti-reflection film) and an anti-finger film (anti-fingerprint film).

The thus obtained lighting device of the present invention has a three-dimensional pattern when turned off and a shading pattern when turned on. Therefore, the lighting device of the present invention has a high degree of design both when it is turned off and when it is turned on.

The lighting device of the present invention can be used in vehicles (private cars, commercial vehicles), buildings (houses, shops such as restaurants), consumer equipment (electronic equipment such as video and audio equipment), furniture, etc. , can be used for decorative lighting. Among them, automobile interior parts are a preferred embodiment of the present invention. Automobile interior parts are visible to users and are used both during the day and at night. When used for such purposes, it is possible to produce different atmospheres in the daytime (when the lights are off) and at night (when the lights are on).

EXAMPLES Hereinafter, the present invention will be described more specifically using examples.

(Resin (for back plate))
・_RB -1: "PC Iupilon H3000UR (transparent)" manufactured by Mitsubishi Engineering-Plastics

(pigment)
・ MB-1: Metallic pigment-containing masterbatch “MB / PCM-A183967-11 L2850 (metallic orange)” manufactured by OK Kasei Co., Ltd.
・ MB-2: Metallic pigment-containing masterbatch “MB / PCM-A1183966-11 L3258 (metallic red)” manufactured by OK Kasei Co., Ltd.
・MB-3: Pigment-containing masterbatch “PC Iupilon MB2218R 8682F (brown: does not contain metallic pigment)” manufactured by Mitsubishi Engineering-Plastics Co., Ltd.

(Resin (for surface plate))
・_RF -1: “ABS Novaloy E80FB-4X2768 (Blue Smoke)” manufactured by Daicel Polymer Co., Ltd.
・_RF -2: “Durabio H0C2F501 (smoke)” manufactured by Mitsubishi Chemical Corporation
・_RF -3: "PC Iupilon H3000UR (transparent)" manufactured by Mitsubishi Engineering-Plastics

(Total light transmittance and haze)
A test piece having a thickness of 2 mm was prepared by injection molding with an injection molding machine using the resin for the back plate or the front plate. Then, the total light transmittance and haze were measured using an ultraviolet-visible spectrophotometer ("V-560" manufactured by JASCO Corporation) equipped with an integrating sphere. Here, the total light transmittance is a value including a decrease due to surface reflection. Table 1 shows the results.

(Evaluation: when the lighting was not turned on)
The design plate was visually observed under an indoor fluorescent lamp without turning on the LED lighting, and the three-dimensional effect, color shading, and matte feeling were evaluated. The three-dimensional effect and color density were evaluated according to the following evaluation criteria. Table 1 shows the results.

・Three-dimensional effect A: A deep three-dimensional pattern was confirmed.
B: A three-dimensional pattern could be confirmed, but the depth of the pattern was somewhat insufficient.
C: Both the three-dimensional effect and the depth of the pattern were slightly insufficient.
D: A three-dimensional pattern could be confirmed, but depth was not felt due to reflection on the uneven surface.
E: The three-dimensional effect of the pattern was insufficient, and depth was not felt due to the reflection on the uneven surface.
F: A three-dimensional pattern could hardly be confirmed.

- Density of Concavo-convex Pattern A: Color densities could be confirmed along the direction perpendicular to the grooves of the concavo-convex pattern. Also, the three-dimensional effect of the pattern changed depending on the observation position.
B: A little color gradation could be confirmed along the direction perpendicular to the uneven grooves.
C: Color density could not be confirmed.

(Appearance evaluation: when lighting is turned on)
The LED lighting was turned on, and the design plate was visually observed and evaluated according to the following evaluation criteria. Table 1 shows the results.
A: A streaky shading pattern was clearly observed.
B: A streaky shading pattern was observed, but somewhat insufficient.
C: A streaky shading pattern was slightly observed.

Example 1
A two-color injection molding machine comprising a common mold having a resin injection path for the first color and a resin injection path for the second color, a first exchangeable mold, and a second exchangeable mold was used. The surface of the first exchange die is provided with an uneven pattern and a stripe pattern smaller than the pitch of the unevenness. By using this first exchange mold, the uneven pattern and the striped pattern are transferred to one surface of the back plate.

First, 100 parts by mass of the above "R _B -1" as a resin for the first color and 2 parts by mass of the above "MB-1" as a masterbatch are blended and put into a hopper (for the first color), then for the second color. As a resin, 100 parts by mass of the above "R _F -1" was put into a hopper (for the second color). Then, by injecting the mixture of the above "R _B -1" and the masterbatch into the back plate cavity formed between the common mold and the first replacement mold, a primary molded body corresponding to the back plate is formed. (See Table 2 for cylinder set temperature, mold temperature, injection speed, and injection pressure).

After cooling for 40 seconds, the first replacement mold was replaced with the second replacement mold. Next, a secondary molded body corresponding to the front plate was formed on the back plate by injecting the above " _RF -1" into the front plate cavity formed between the back plate and the second replacement mold. (See Table 2 for cylinder set temperature, mold temperature, injection speed, and injection pressure). Then, the common mold and the second replacement mold were cooled, and the design plate was removed from the common mold and the second replacement mold.

The shape of the obtained design plate is shown in FIG. 2 is a schematic cross-sectional view taken along line AA of FIG. 1, and FIG. 3 is an enlarged view of a portion (B) surrounded by a square in the schematic cross-sectional view along line AA of FIG. As shown in FIGS. 2 and 3, the back plate 1 had rounded wavy irregularities on one surface thereof. The pitch of the unevenness was about 5 to 8 mm, and about 5 to 8 streak patterns were confirmed in each of the grooves of the unevenness. On the other hand, one surface of the front plate 2 was in contact with the irregularities, and the other surface was smooth. Moreover, the thickness of the entire design plate was uniform.

Table 1 shows the total light transmittance (Y), maximum thickness and minimum thickness of the back plate 1, total light transmittance (X) of the front plate 2, haze, and thickness of the decorative plate.

LED lighting was then prepared. This LED illumination is an illumination that can irradiate diffused light by arranging a white LED light source on the back side of the light diffusion plate. A lighting device was obtained by using this LED lighting and the design plate, and installing the back plate and the LED lighting facing each other. Then, the LED lighting was turned on and off, and the design plate was visually observed and evaluated according to the above evaluation criteria. Table 1 shows the results.

Examples 2-12
A design plate was obtained in the same manner as in Example 1 except that the type of resin was changed as shown in Table 1, and the cylinder set temperature, mold temperature, injection speed, and injection pressure were changed as shown in Table 2. It was used for evaluation. Table 1 shows the results. 4 and 6 show photographs of the external appearance of the lighting devices of Examples 4 and 6 when turned off, and FIGS. 5 and 7 show photographs of the external appearance when turned on.

Example 13
A design plate was obtained in the same manner as in Example 1, except that the type of resin was changed as shown in Table 1, and the cylinder set temperature, mold temperature, injection speed, and injection pressure were changed as shown in Table 2. . Then, characters were printed on the surface of the obtained design board facing the light irradiation means (the surface of the back surface board), and the design board was used for evaluation. Table 1 shows the results. As shown in FIGS. 10 and 11, when the LED illumination was turned on, characters that were not displayed when the LED was turned off were displayed on the surface of the design plate.

Comparative Examples 1 and 2
The type of resin was changed as shown in Table 1, the cylinder set temperature, mold temperature, injection speed, and injection pressure were changed as shown in Table 2, and secondary molding was not performed. Similarly, a design plate without a front plate was obtained and evaluated using this. Table 1 shows the results.

Comparative example 3
In the same manner as in Example 1, except that the type of resin was changed as shown in Table 1, and the cylinder set temperature, mold temperature, injection speed, and injection pressure were changed as shown in Table 2, the back plate was made of a metallic pigment. A design board containing no was obtained and evaluated using this. Table 1 shows the results.

1 back plate 2 front plate

Claims (13)

A lighting device comprising a design plate formed by laminating a back plate and a front plate, and light irradiation means;
The back plate is made of a resin composition containing a metallic pigment or a pearl pigment, and has unevenness on one surface thereof,
One surface of the front plate is in contact with the unevenness and the other surface is flat,
The back plate is arranged in a direction facing the light irradiation means,
The resin constituting the front plate has a total light transmittance (X) of 20 to 100%/2 mm, and the resin constituting the back plate has a total light transmittance (Y) of 0.1 to 80%/2 mm. A lighting device characterized by: 2. The lighting device according to claim 1, wherein the surface of the back plate further has a stripe pattern, and the pitch of the stripe pattern is smaller than the pitch of the unevenness. The maximum thickness (A) of the back plate is 1 to 20 mm, the minimum thickness (B) is 0.5 to 10 mm,
3. The lighting device according to claim 1, wherein the difference between the thickness (A) and the thickness (B) is 0.5 mm or more. The lighting device according to any one of claims 1 to 3, wherein the pitch of the unevenness is 0.5 to 20 mm. 5. The lighting device according to any one of claims 1 to 4, wherein the thickness of the back plate gradually changes. The lighting device according to any one of claims 1 to 5, wherein the design plate has a thickness of 2 to 30 mm. The lighting device according to any one of claims 1 to 6, wherein the front plate is made of a resin having a haze of 90% or less. The illumination device according to any one of claims 1 to 7, wherein the light irradiation means irradiates diffused light. 9. The illumination device according to claim 8, wherein said light irradiation means has a light diffusion plate and a light source. 10. The lighting device according to any one of claims 1 to 9, wherein a light shielding pattern is formed between said back plate and said light irradiation means. 10. The illumination device according to any one of claims 1 to 9, wherein said light irradiation means includes pattern information. An automobile interior part comprising the lighting device according to any one of claims 1 to 11. A method for manufacturing a lighting device according to any one of claims 1 to 12;
Step 1 of forming the back plate by injecting and filling a resin composition containing a metallic pigment or a pearl pigment into a cavity for the back plate formed between the common mold and the first replacement mold;
Step 2 of exchanging the first exchange mold for a second exchange mold;
a step 3 of injecting and filling a resin into a front plate cavity formed between the back plate and the second replacement mold to form the front plate;
a step 4 of cooling the common mold and the second replacement mold and removing the design plate from the common mold and the second replacement mold;
A method of manufacturing a lighting device, comprising step 5 of arranging the design plate so that the back plate faces the light irradiation means.

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