Molded body and display device

Abstract

The present invention provides a molded body that has an excellent jet black color when the light source is off, can present a specific color tone when the light source is on, and has high solar transmittance. The molded body of the present invention comprises a transparent resin, the L* value of reflected light is 35 or less, and the wavelength of the light transmittance showing a maximum value in the range of wavelengths from 430 nm to 700 nm is in the range of 430 nm to less than 680 nm, and the transmittance of light at a wavelength of 770 nm is 0.5% or more.

Description

Technical Field

[0001] The present invention relates to a molded body and a display device.

[0002] This application claims priority based on Japanese Patent Application No. 2020-052857 filed in Japan on March 24, 2020, the contents of which are incorporated herein by reference. Background Art

[0003] In the applications of vehicle interior and exterior components, lighting lamps, and display signs (hereinafter referred to as "vehicle interior and exterior components, etc."), there is a demand for display devices that display the color tone and given information required by the market. In the above applications, since excellent appearance and weather resistance are required, molded bodies formed of thermoplastic resins such as methacrylic resins and polycarbonate resins are used.

[0004] In recent years, in applications such as vehicle interior and exterior components, there is a demand for thermoplastic resin molded products that can present a black achromatic color tone (jet black) when the light source is off to make the presence disappear and the surface height differences and seams become less noticeable, while on the other hand, can present a colorful or achromatic color tone when the light source is on to exert a presence, that is, excellent in design.

[0005] Here, when a dye having an absorption band in the wavelength range of 380 to 780 nm is added to a transparent thermoplastic resin such as a methacrylic resin in order to impart a colored or achromatic hue to the molded body when the light source is turned on, although the solar transmittance does not change in the wavelength range of more than 780 nm and less than 2100 nm, the solar transmittance decreases in the wavelength range of 380 to 780 nm, which is the light absorption band of the dye. On the other hand, the solar reflectance is lower than the solar transmittance and shows a certain value in the wavelength range of 380 to 2100 nm. That is, by adding the above-mentioned dye, the solar absorptivity increases, and the solar absorptivity is the value obtained by subtracting the solar transmittance and the solar reflectivity from 100%. As a result, the higher the solar absorptivity of the thermoplastic resin molded body, the higher the risk of thermal deformation, denaturation or thermal cracking of the thermoplastic resin molded body as the temperature rises. That is, in order to suppress thermal cracking and the like, a thermoplastic resin molded body having a low solar absorptivity, in other words, a thermoplastic resin molded body having a high solar transmittance is required.

[0006] As a method for imparting jet-black properties to thermoplastic resin molded products, for example, Patent Document 1 discloses a resin molded product blended with carbon black. Also, Patent Document 2 discloses a resin molded product blended with an organic dye.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Publication No. 2011-12247

[0010] Patent Document 2: International Publication No. 2016 / 098746 Summary of the invention

[0011] Problems to be solved by the invention

[0012] The resin molded article disclosed in Patent Document 1 exhibits a jet black color when the light source is off, but it is difficult to exhibit a color or achromatic color tone when the light source is on, that is, the designability is insufficient.

[0013] The resin molded article disclosed in Patent Document 2 has an excellent jet black color when the light source is off and can exhibit a specific color tone when the light source is on. Therefore, it has excellent design properties, but has a problem of low solar transmittance.

[0014] Under such circumstances, an object of the present invention is to provide a molded body that has an excellent jet-black color when a light source is off, can exhibit a specific color tone when the light source is on, and has a high solar transmittance.

[0015] Solution to the problem

[0016] The first subject of the present invention relates to a molded body comprising a transparent resin, wherein the L* value of reflected light is less than 35, and in the wavelength range of greater than 430 nm and less than 700 nm, the wavelength at which the transmittance of light shows a maximum value is within the range of greater than 430 nm and less than 680 nm, and the transmittance of light at a wavelength of 770 nm is greater than 0.5%.

[0017] The following aspects can be mentioned as aspects of the present invention, but the present invention is not limited thereto.

[0018] [1] A molded article comprising a transparent resin,

[0019] The L* value of reflected light of the molded article is 35 or less, and

[0020] In the wavelength range of 430 nm to 700 nm, the wavelength at which the light transmittance shows a maximum value is in the range of 430 nm to less than 680 nm.

[0021] The transmittance of light at a wavelength of 770 nm is 0.5% or more.

[0022] [2] The molded article according to [1], comprising two or more light absorbers (L), wherein the two or more light absorbers (L) have different wavelengths at which absorbance exhibits maximum values ​​within a wavelength range of 380 nm to 730 nm.

[0023] [3] The molded article according to [2], comprising, as the light absorber (L), a light absorber (B) having a wavelength at which absorbance shows a maximum value within a range of 630 nm to 700 nm.

[0024] [4] The molded article according to [2] or [3], wherein the light absorber (L) does not contain a light absorber having a wavelength exceeding 720 nm at which the absorbance shows a maximum value.

[0025] [5] The molded article according to any one of [1] to [4], wherein the total light transmittance is less than 5%.

[0026] [6] The molded article according to any one of [1] to [5], wherein the maximum value of the light transmittance at the wavelength at which the light transmittance shows a maximum value in the wavelength range of 430 nm to 700 nm is 0.1% or more.

[0027] [7] The molded article according to any one of [1] to [6], wherein the transmittance of light at a wavelength of 770 nm is 1% or more.

[0028] [8] The molded article according to any one of [1] to [7], wherein the transparent resin is a methacrylic resin.

[0029] [13A] The molded article according to any one of [2] to [4], wherein the light absorber (L) satisfies any one of the following conditions 1 or 2.

[0030] Condition 1:

[0031] There is only one i that satisfies the following formula (5), and satisfies the following formula (6).

[0032] Formula (5):

[0033] λ(i+1)-λ(i)≥160nm···(5)

[0034] Formula (6):

[0035] λ(1)-380nm<160nm···(6)

[0036] Condition 2:

[0037] The following formula (5) is not satisfied, but the following formula (7) is satisfied.

[0038] Formula (5):

[0039] λ(i+1)-λ(i)≥160nm···(5)

[0040] Formula (7):

[0041] λ(1)-380nm≥160nm···(7)

[0042] [In the formula, λ(i) is the wavelength at which the light absorber (i) as one of the light absorbers (L) shows a maximum absorbance in the wavelength range of 380 nm to 730 nm, i is an integer from 1 to n, n is an integer of 2 or more and represents the number of types of the light absorber (L), λ(n+1) is 730 nm, λ(1)<λ(2)<···<λ(n)<λ(n+1).]

[0043]

[14] The molded article according to any one of [2] to [4], comprising, as the light absorber (L), a light absorber (A) having a wavelength at which absorbance exhibits a maximum value in the range of 400 nm to less than 630 nm.

[0044] [16A] The molded article according to

[14] , wherein the light absorber (A) comprises a light absorber selected from anthraquinone pigments and phthalocyanine pigments.

[0045] The second aspect of the present invention relates to a molded article obtained by molding a thermoplastic resin composition, the thermoplastic resin composition comprising a methacrylic resin and two or more light absorbers (L), the two or more light absorbers (L) having different wavelengths at which absorbances show a maximum value in the wavelength range of 380 nm to 730 nm, wherein the light absorber (L) comprises a light absorber (B) having a wavelength at which absorbance shows a maximum value in the wavelength range of 630 nm to 700 nm, the molded article having an L* value of reflected light of 35 or less, a total light transmittance of 1% or less, a wavelength at which light transmittance shows a maximum value in the wavelength range of 430 nm to 700 nm, a maximum value of light transmittance at a wavelength at which light transmittance shows a maximum value in the wavelength range of 430 nm to 700 nm, and a light transmittance of 5% or more at a wavelength of 770 nm.

[0046] The following aspects can be mentioned as aspects of the present invention, but the present invention is not limited thereto.

[0047] [9] A molded article obtained by molding a thermoplastic resin composition, the thermoplastic resin composition comprising a methacrylic resin and two or more light absorbers (L), the two or more light absorbers (L) having different wavelengths at which absorbances show maximum values ​​in a wavelength range of 380 nm to 730 nm, wherein:

[0048] The light absorber (L) includes a light absorber (B) having a wavelength at which the absorbance shows a maximum value within a range of 630 nm to 700 nm.

[0049] The L* value of the reflected light of the molded body is 35 or less,

[0050] The total light transmittance is less than 1%,

[0051] In the wavelength range of 430 nm to 700 nm, the wavelength at which the light transmittance shows a maximum value is in the range of 430 nm to less than 680 nm.

[0052] The maximum value of the light transmittance at the wavelength at which the light transmittance shows a maximum value in the wavelength range of 430 nm to 700 nm is 0.1% or more,

[0053] The transmittance of light at a wavelength of 770 nm is 5% or more.

[0054]

[10] The molded article according to [9], wherein the light absorber (B) comprises a light absorber selected from anthraquinone dyes, pyrene dyes, methine dyes, and quinophthalone dyes.

[0055]

[11] The molded article according to [9] or

[10] , wherein the total content of the light absorber (B) is 0.1 part by mass or more and 0.5 part by mass or less based on 100 parts by mass of the methacrylic resin.

[0056]

[12] The molded article according to any one of [9] to

[11] , wherein the light absorber (L) does not contain a light absorber having a wavelength exceeding 720 nm at which the absorbance shows a maximum value.

[0057] [13B] The molded article according to any one of [9] to

[12] , wherein the light absorber (L) satisfies any one of the following conditions 1 or 2.

[0058] Condition 1:

[0059] There is only one i that satisfies the following formula (5), and satisfies the following formula (6).

[0060] Formula (5):

[0061] λ(i+1)-λ(i)≥160nm···(5)

[0062] Formula (6):

[0063] λ(1)-380nm<160nm···(6)

[0064] Condition 2:

[0065] The following formula (5) is not satisfied, but the following formula (7) is satisfied.

[0066] Formula (5):

[0067] λ(i+1)-λ(i)≥160nm···(5)

[0068] Formula (7):

[0069] λ(1)-380nm≥160nm···(7)

[0070] [In the formula, λ(i) is the wavelength at which the light absorber (i) as one of the light absorbers (L) shows a maximum absorbance in the wavelength range of 380 nm to 730 nm, i is an integer from 1 to n, n is an integer of 2 or more and represents the number of types of the light absorber (L), λ(n+1) is 730 nm, λ(1)<λ(2)<···<λ(n)<λ(n+1).]

[0071]

[15] The molded article according to any one of [9] to [13B], comprising, as the light absorber (L), a light absorber (A) having a wavelength at which absorbance exhibits a maximum value in the range of 400 nm to less than 630 nm,

[0072] The total content of the light absorber (A) is 0.001 parts by mass or more and 1 part by mass or less relative to 100 parts by mass of the methacrylic resin.

[0073] [16B] The molded article according to

[15] , wherein the light absorber (A) comprises a light absorber selected from anthraquinone pigments and phthalocyanine pigments.

[0074] A third aspect of the present invention relates to a display device including a light source and a molded body of the present invention, wherein the molded body of the present invention is arranged so that light emitted from the light source passes through the molded body.

[0075] Effects of the Invention

[0076] The molded article of the present invention has an excellent jet black color when the light source is off, can present a specific color tone when the light source is on, and has a high solar transmittance. Therefore, the molded article of the present invention is not easy to store heat, and is not easy to deform, change, or heat crack due to heat.

[0077] Regarding the display device of the present invention, since the molded body of the present invention is arranged so that the light emitted by the light source transmits through the molded body, the color is excellent in jet black when the light source is off, and a specific color tone can be presented when the light source is on, and the sunlight transmittance is high. Therefore, the display device of the present invention is not easy to store heat, and is not easy to deform, change, or heat crack due to heat. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] Figure 1 It is a schematic diagram showing an example of the display device of the present invention.

[0079] Figure 2 This is a graph showing the transmittance of the molded article of Example 1 with respect to light having a wavelength of 380 nm to 780 nm.

[0080] Figure 3 This is a graph showing the transmittance of the molded article of Example 2 with respect to light having a wavelength of 380 nm to 780 nm.

[0081] Figure 4 This is a graph showing the transmittance of the molded article of Example 3 with respect to light having a wavelength of 380 nm to 780 nm.

[0082] Figure 5 This is a graph showing the transmittance of the molded article of Example 4 with respect to light having a wavelength of 380 nm to 780 nm.

[0083] Figure 6 This is a graph showing the transmittance of the molded article of Comparative Example 1 with respect to light having a wavelength of 380 nm to 780 nm.

[0084] Figure 7 This is a graph showing the transmittance of the molded article of Comparative Example 2 with respect to light having a wavelength of 380 nm to 780 nm.

[0085] Figure 8 This is a graph showing the transmittance of the molded article of Comparative Example 3 with respect to light having a wavelength of 380 nm to 780 nm.

[0086] Fig. 9 This is a graph showing the transmittance of the molded article of Example 5 with respect to light having a wavelength of 380 nm to 780 nm.

[0087] Explanation of symbols

[0088] 1 Display device

[0089] 10 Light Source

[0090] 12 Molding

[0091] 20 Light from a light source

[0092] 22 Light emitted from the light source and transmitted through the molded body DETAILED DESCRIPTION

[0093] Hereinafter, embodiments of the present invention will be described.

[0094] <Molding body>

[0095] The first embodiment of the molded body of the present invention is a molded body (hereinafter also referred to as molded body (1)), which contains a transparent resin, has an L* value of reflected light of less than 35, and in the wavelength range of greater than 430nm and less than 700nm, the wavelength at which the transmittance of light shows a maximum value is in the range of greater than 430nm and less than 680nm, and the transmittance of light at a wavelength of 770nm is greater than 0.5%.

[0096] The molded article (1) of the present invention has an excellent jet-black color when the light source is off. When the light source, especially the white light source, is on, the light emitted by the white light source passes through the molded article (1). At this time, light of a specific wavelength can be selectively transmitted to present a specific color tone.

[0097] Here, white light refers to light that appears white because a plurality of wavelengths of light are mixed together, and colored light refers to light of a specific wavelength (eg, red light, blue light) in the visible light wavelength range.

[0098] In order to make the obtained molded article excellent in jet blackness, preferably excellent in transparency, the molded article (1) of the present invention contains a transparent resin described later, thereby making the obtained molded article excellent in jet blackness.

[0099] The L* value of reflected light of the molded article (1) of the present invention is 35 or less. When the L* value of reflected light is 35 or less, the molded article has excellent jet-black properties. Preferably, it is 30 or less.

[0100] In the present invention, the L* value of reflected light is calculated based on tristimulus values ​​X, Y, and Z measured by spectrophotometry (integrating sphere type, reflectance measurement) in accordance with ISO11664-4.

[0101] In the molded article (1) of the present invention, the wavelength at which the transmittance of light shows a maximum value in the wavelength range of 430 nm to 700 nm is in the range of 430 nm to less than 680 nm. In the wavelength range of 430 nm to 700 nm, by making the wavelength at which the transmittance of light shows a maximum value in the range of 430 nm to less than 680 nm, light with a wavelength in the range of 430 nm to less than 680 nm can be selectively transmitted, thereby presenting a specific color tone.

[0102] The lower limit of the transmittance of the molded article (1) of the present invention at a wavelength of 770 nm is 0.5% or more. When the transmittance of light at a wavelength of 770 nm is 0.5% or more, the solar transmittance of the obtained molded article is high. Therefore, it is not easy to store heat, and deformation, denaturation, and thermal cracking caused by heat are not easy to occur. The lower limit is preferably 1% or more, more preferably 5% or more, further preferably 20% or more, further preferably 40% or more, and particularly preferably 60% or more.

[0103] The upper limit of the transmittance of light at a wavelength of 770 nm is not particularly limited, but is preferably 90% or less. When the transmittance of light at a wavelength of 770 nm is 90% or less, the blackness of the molded body is excellent. The upper limit is more preferably 80% or less, and further preferably 75% or more.

[0104] The above upper and lower limits may be combined arbitrarily. For example, the transmittance of the molded article (1) at a wavelength of 770 nm is preferably 0.5% to 90%, more preferably 1% to 90%, further preferably 5% to 80%, and particularly preferably 20% to 75%.

[0105] The molded article (1) of the present invention preferably contains two or more light absorbers (L) having wavelengths different from each other at which absorbance exhibits a maximum value within a wavelength range of 380 nm to 730 nm.

[0106] When the molded article (1) of the present invention contains two or more light absorbers (L), the light absorber (L) preferably contains a light absorber (B) having a wavelength showing a maximum absorbance in the range of 630 nm to 700 nm.

[0107] By including the light absorber (B), the obtained molded article can selectively transmit light of a specific wavelength when the light source is turned on, thereby exhibiting a specific color tone, and thus the color selectivity of the transmitted light is excellent. The light absorber (B) will be described later.

[0108] The upper limit of the total light transmittance of the molded article (1) of the present invention is preferably less than 5%. When the total light transmittance is less than 5%, the molded article has excellent jet-black properties. The upper limit is more preferably 3% or less, and further preferably 1% or less.

[0109] The lower limit of the total light transmittance is preferably 0.01% or more. When the total light transmittance is 0.01% or more, colored light can be formed by transmitting light emitted from a light source, such as a white light source, through the molded body. The lower limit is more preferably 0.02% or more, and even more preferably 0.04% or more.

[0110] For example, the total light transmittance of the molded article (1) is preferably 0.01% or more and less than 5%, more preferably 0.02% or more and 3% or less, and even more preferably 0.04% or more and 1% or less.

[0111] In the molded article (1) of the present invention, the lower limit of the maximum value of the light transmittance at the wavelength where the light transmittance shows a maximum value in the wavelength range of 430 nm to 700 nm is preferably 0.1% or more. By setting the maximum value of the light transmittance at the wavelength where the light transmittance shows a maximum value to 0.1% or more in the wavelength range of 430 nm to 700 nm, light of a specific wavelength in the range of 430 nm to less than 680 nm can be selectively transmitted, thereby presenting a specific color tone. The lower limit is more preferably 0.15% or more, and further preferably 0.22% or more.

[0112] The upper limit of the maximum value of the light transmittance at the wavelength where the light transmittance shows a maximum value in the range of wavelengths from 430 nm to 700 nm is not particularly limited, but is preferably 5.0% or less. When the maximum value of the light transmittance at the wavelength where the light transmittance shows a maximum value in the range of wavelengths from 430 nm to 700 nm is 5.0% or less, the blackness of the molded article is excellent. The upper limit is more preferably 2.0% or less, and further preferably 1.0% or less.

[0113] The above upper and lower limits may be combined arbitrarily. For example, the transmittance of light at the wavelength at which the transmittance of light in the range of wavelength from 430 nm to 700 nm of the molded article (1) shows a maximum value is preferably from 0.1% to 5.0%, more preferably from 0.15% to 2.0%, and even more preferably from 0.22% to 1.0%.

[0114] In the molded article (1) of the present invention, it is preferred that the light absorber (L) does not contain a light absorber whose absorbance shows a maximum value at a wavelength exceeding 720 nm. By not containing a light absorber whose absorbance shows a maximum value at a wavelength exceeding 720 nm, the solar transmittance of the obtained molded article (1) can be improved more efficiently. Therefore, the molded article (1) is less likely to store heat, and is less likely to be deformed, denatured, or thermally cracked due to heat.

[0115] As one embodiment of the transparent resin contained in the molded article (1) of the present invention, a methacrylic resin described below can be mentioned.

[0116] When the transparent resin is a methacrylic resin, the obtained molded product has excellent transparency and, as a result, excellent jet-blackness.

[0117] The second embodiment of the molded article of the present invention is a molded article (2) obtained by molding the thermoplastic resin composition described later.

[0118] The L* value of reflected light of the molded article (2) of the present invention is 35 or less, the total light transmittance is 1% or less, and in the wavelength range of 430 nm to 700 nm, the wavelength at which the light transmittance shows a maximum value is in the range of 430 nm to less than 680 nm. In the wavelength range of 430 nm to 700 nm, the maximum value of the light transmittance at the wavelength at which the light transmittance shows a maximum value is 0.1% or more, and the light transmittance at a wavelength of 770 nm is 5% or more.

[0119] The molded product (2) of the present invention has an excellent jet-black color when the light source is off. When the light source, especially a white light source, is on, the light emitted from the white light source is transmitted through the molded product (2). At this time, light of a specific wavelength can be selectively transmitted to present a specific color tone.

[0120] The L* value of reflected light of the molded article (2) of the present invention is 35 or less, preferably 30 or less. When the L* value of reflected light of the molded article is below the above upper limit, the molded article has excellent blackness.

[0121] In the present invention, the L* value of reflected light is calculated from tristimulus values ​​X, Y, and Z measured by spectrophotometry (integrating sphere type, reflectance measurement) in accordance with ISO11664-4.

[0122] The upper limit of the total light transmittance of the molded article (2) of the present invention is 1% or less. When the total light transmittance is 1% or less, the blackness of the molded article is excellent. The upper limit is preferably 0.5% or less.

[0123] The lower limit of the total light transmittance is preferably 0.01% or more. When the total light transmittance is 0.01% or more, colored light can be formed by transmitting light emitted from a light source, such as a white light source, through the molded body. The lower limit is more preferably 0.02% or more, and even more preferably 0.04% or more.

[0124] The above upper and lower limits may be combined arbitrarily. For example, the total light transmittance of the molded article (2) is preferably 0.01% to 1%, and more preferably 0.02% to 0.5%.

[0125] In the present invention, the transmittance of light in the visible light wavelength range, that is, the total light transmittance is measured in accordance with ISO 13468-1. It should be noted that the total light transmittance of the molded article of the present invention may sometimes reach a low value exceeding the detection limit, but in the present invention, as long as the color of the light emitted from the light source and transmitted through the molded article can be confirmed by naked eye observation, it is not necessary to have a molded article in which the color of the light emitted from the light source and transmitted through the molded article cannot be confirmed by naked eye observation.

[0126] In the molded article (2) of the present invention, the wavelength at which the transmittance of light shows a maximum value in the wavelength range of 430 nm to 700 nm is in the range of 430 nm to less than 680 nm. In the wavelength range of 430 nm to 700 nm, by making the wavelength at which the transmittance of light shows a maximum value in the range of 430 nm to less than 680 nm, light with a wavelength in the range of 430 nm to less than 680 nm can be selectively transmitted, thereby presenting a specific color tone.

[0127] In the molded article (2) of the present invention, the lower limit of the maximum value of the light transmittance at the wavelength where the light transmittance shows a maximum value in the wavelength range of 430 nm to 700 nm is 0.1% or more. In the wavelength range of 430 nm to 700 nm, by setting the lower limit of the maximum value of the light transmittance at the wavelength where the light transmittance shows a maximum value to 0.1% or more, light of a specific wavelength in the range of 430 nm to less than 680 nm can be selectively transmitted, thereby presenting a specific color tone. The lower limit is more preferably 0.15% or more, and even more preferably 0.22% or more.

[0128] The upper limit of the maximum value of the light transmittance at the wavelength where the light transmittance shows a maximum value in the range of wavelengths from 430 nm to 700 nm is not particularly limited, but is preferably 5.0% or less. When the maximum value of the light transmittance at the wavelength where the light transmittance shows a maximum value in the range of wavelengths from 430 nm to 700 nm is 5.0% or less, the blackness of the molded article is excellent. The upper limit is more preferably 2.0% or less, and further preferably 1.0% or less.

[0129] The above upper and lower limits may be combined arbitrarily. For example, the transmittance of light at the wavelength at which the transmittance of light in the range of wavelength of 430 nm to 700 nm of the molded article (2) shows a maximum value is preferably 0.1% to 5.0%, more preferably 0.15% to 2.0%, and even more preferably 0.22% to 1.0%.

[0130] The lower limit of the transmittance of light at a wavelength of 770 nm of the molded article (2) of the present invention is 5% or more. When the transmittance of light at a wavelength of 770 nm is 5% or more, the solar transmittance of the obtained molded article is high. Therefore, it is not easy to store heat, and deformation, denaturation, and thermal cracking caused by heat are not easy to occur. The lower limit is preferably 20% or more, more preferably 40% or more, and even more preferably 60% or more.

[0131] The upper limit of the transmittance of light at a wavelength of 770 nm is not particularly limited, but is preferably 90% or less. When the transmittance of light at a wavelength of 770 nm is 90% or less, the blackness of the molded body is excellent. The upper limit is more preferably 80% or less, and further preferably 75% or more.

[0132] For example, the light transmittance of the molded article (2) at a wavelength of 770 nm is preferably 5% to 90%, more preferably 20% to 80%, and even more preferably 40% to 75%.

[0133] In the present invention, the transmittance of light in the wavelength range of 380 nm to 770 nm is obtained by transmitting light with a wavelength of 380 nm to 780 nm from the back side of the molded article and measuring the light transmitted from the surface of the molded article using a spectrophotometer.

[0134] The thermoplastic resin composition used for the molded body (2) of the present invention contains two or more light absorbers (L) whose wavelengths of absorbance showing a maximum value are different from each other within a wavelength range of 380 nm to 730 nm. As the light absorber (L), a light absorber (B) whose wavelength of absorbance showing a maximum value is within a range of 630 nm to 700 nm is contained. In the molded body (2) of the present invention, as the light absorber (L), it is preferred that no light absorber whose wavelength of absorbance showing a maximum value is within a range of more than 720 nm is contained. By not containing a light absorber whose wavelength of absorbance showing a maximum value is within a range of more than 720 nm, the solar transmittance of the obtained molded body (2) can be more efficiently improved. Therefore, the molded body is not easy to store heat, and deformation, denaturation, and thermal cracking caused by heat are not easy to occur.

[0135] The thickness of the molded body (2) of the present invention in the transmission direction of light emitted from the light source is preferably 0.01 mm to 100 mm, more preferably 0.1 mm to 10 mm. When the thickness of the molded body is above the lower limit, the blackness of the molded body is excellent, and when it is above the upper limit, the transmitted light intensity of the molded body is excellent.

[0136] [Method for producing molded article]

[0137] The method for producing the molded product (1) and the molded product (2) of the present invention will be described.

[0138] The molded article (1) of the present invention is preferably a molded article obtained by molding a resin composition containing a transparent resin and a light absorber (L) described below. The molded article (2) of the present invention is preferably a molded article obtained by molding a thermoplastic resin composition of the present invention described below.

[0139] As a method for molding the molded body, a known method can be adopted, and examples thereof include molding methods based on extrusion molding, injection molding, blow molding, and press molding.

[0140] <Thermoplastic resin composition>

[0141] The thermoplastic resin composition is one of the constituent components of the molded article (2) of the present invention.

[0142] The thermoplastic resin composition of the present invention contains a methacrylic resin and a light absorber (L) as described below.

[0143] <Transparent resin>

[0144] The transparent resin is one of the constituent components of the molded article (1) of the present invention.

[0145] The transparent resin used in the molded body (1) of the present invention is not particularly limited as long as it has a high light transmittance in the visible light region, and a known transparent thermoplastic resin can be used. For example, transparent thermoplastic resins having a total light transmittance of 70% or more as measured in accordance with ISO13468 and a haze value of 15% or less as measured in accordance with ISO14782 can be cited. Specifically, methacrylic resins, polycarbonate resins, polystyrene resins, and methyl methacrylate-styrene resins (MS resins) can be cited. In the molded body (1) of the present invention, one of these transparent thermoplastic resins selected according to the desired characteristics can be used alone, or two or more can be mixed and used. In particular, methacrylic resins are excellent in transparency, weather resistance, and impact resistance.

[0146] The weight average molecular weight and number average molecular weight of the transparent resin can be appropriately set by a person skilled in the art according to a known technique, for example, the molding method, processing conditions, and intended use of the molded product.

[0147] The transparent resin may contain additives such as an impact strength modifier, a mold release agent, an ultraviolet absorber, a polymerization inhibitor, an antioxidant, and a flame retardant within a range that does not impair the effects of the present invention.

[0148] [Methacrylic resin]

[0149] The methacrylic resin is one embodiment of the transparent resin used in the molded article (1) of the present invention. The methacrylic resin is one of the constituent components of the thermoplastic resin composition used in the molded article (2) of the present invention.

[0150] Examples of the methacrylic resin include homopolymers of methyl methacrylate (hereinafter referred to as "MMA") and MMA copolymers in which the content of repeating units derived from MMA (hereinafter referred to as "MMA units") is 70% by mass or more and less than 100% by mass based on the total mass of the methacrylic resin.

[0151] The MMA copolymer of the present invention contains 70% by mass or more and less than 100% by mass of MMA units and more than 0% by mass but less than 30% by mass of repeating units derived from other monomers described later (hereinafter referred to as "other monomer units").

[0152] There are no particular limitations on other monomers as long as they can be copolymerized with MMA, and examples thereof include known (meth)acrylate compounds such as methyl acrylate, ethyl (meth)acrylate, and n-butyl (meth)acrylate, and known aromatic vinyl compounds such as styrene and α-methylstyrene.

[0153] Examples of commercially available products of the methacrylic resin include ACRYPET (registered trademark) VH, ACRYPET MD, and ACRYPET MF (all trade names, manufactured by Mitsubishi Chemical Corporation).

[0154] [Light absorber (L)]

[0155] The molded article (1) of the present invention may contain a light absorber (L) as one of the constituent components. In addition, the molded article (2) of the present invention contains a light absorber (L) as one of the constituent components of the thermoplastic resin composition.

[0156] The light absorber (L) includes two or more light absorbers having wavelengths different from each other at which the absorbance shows a maximum value in the wavelength range of 380 nm to 730 nm. By including two or more light absorbers, the total light transmittance of the molded body can be effectively reduced. Therefore, a molded body with better blackness can be obtained.

[0157] In the molded article (1) of the present invention, as the light absorber (L), a light absorber (B) having a wavelength at which the absorbance shows a maximum value in the range of 630 nm to 700 nm may be included. In the molded article (2) of the present invention, the light absorber (L) includes the light absorber (B). By including the light absorber (B), the obtained molded article can selectively transmit light of a specific wavelength when the light source is turned on, exhibit a specific color tone, and has excellent selectivity in the color of the transmitted light.

[0158] As the light absorber (L), it is preferred that no light absorber is included whose absorbance shows a maximum value at a wavelength exceeding 720 nm. By not including a light absorber whose absorbance shows a maximum value at a wavelength exceeding 720 nm, the solar transmittance of the obtained molded body can be improved more efficiently. Therefore, the molded body is less likely to store heat, and deformation, denaturation, and thermal cracking caused by heat are less likely to occur.

[0159] By including the light absorber (B) as the light absorber (L), such an effect can be obtained more effectively.

[0160] As the light absorber (L) of the present invention, a light absorber (A) may be included. As the light absorber (L), by including a light absorber (A) in addition to the light absorber (B), the total light transmittance of the molded body can be effectively reduced. Therefore, a molded body with better blackness can be obtained.

[0161] In the present invention, absorbance is measured using a spectrophotometer.

[0162] (Light absorber (A))

[0163] The light absorber (A) is a light absorber having a wavelength at which the absorbance shows a maximum value in the range of 400 nm or more and less than 630 nm.

[0164] By including the light absorber (A) as the light absorber (L), the obtained molded article can combine the effects of the light absorber (B) to more effectively selectively transmit light of a specific wavelength when the light source is turned on, thereby exhibiting a specific color tone.

[0165] As the light absorber (A), for example, near infrared absorbing pigments can be mentioned. As the near infrared absorbing pigments, for example, anthraquinone pigments and phthalocyanine pigments can be mentioned. Among the light absorbers (A), from the viewpoint of excellent transparency and weather resistance of the molded body, anthraquinone pigments as near infrared absorbing pigments are preferred.

[0166] The light absorber (A) may be used alone or in combination of two or more.

[0167] Examples of the light absorber (A) include SDO series manufactured by Honkagaku Kogyo Co., Ltd., EXCOLOR (registered trademark) series manufactured by Nippon Shokubai Co., Ltd., and KAYASORB (registered trademark) series manufactured by Nippon Kayaku Co., Ltd.

[0168] When a light absorber (A) is included, its content (the total amount thereof when two or more are used in combination) can be 0.001 to 1 part by mass, preferably 0.01 to 0.5 parts by mass, relative to 100 parts by mass of the transparent resin in the molded article (1) of the present invention and 100 parts by mass of the methacrylic resin in the molded article (2) of the present invention. When the content of the light absorber (A) is at least the lower limit, the color selectivity of the transmitted light of the molded article is excellent. When it is at most the upper limit, the transmitted light intensity of the molded article is excellent.

[0169] (Light absorber (B))

[0170] The light absorber (B) is a light absorber having a wavelength at which the absorbance shows a maximum value within a range of 630 nm to 700 nm.

[0171] By including the light absorber (B) as the light absorber (L), the obtained molded article has excellent color selectivity of transmitted light.

[0172] As the light absorber (B), for example, dyes can be mentioned. As dyes, for example, anthraquinone dyes, pyrene dyes, methine dyes, and quinophthalone dyes can be mentioned. Among the light absorbers (B), anthraquinone dyes and pyrene dyes are preferred as dyes from the viewpoint of excellent weather resistance of the molded body.

[0173] The light absorber (B) may be used alone or in combination of two or more.

[0174] Examples of the anthraquinone dye include dyes of color indexes such as Solvent Blue 87, Solvent Blue 94, Solvent Blue 97, Solvent Green 3, Solvent Green 28, Solvent Red 52, Solvent Red 111, Disperse Red 22, Solvent Violet 13, and Solvent Violet 36.

[0175] Examples of the pyrenone dye include color index dyes such as Solvent Orange 60, Solvent Red 135, and Solvent Red 179.

[0176] Examples of the methine dye include color index dyes such as Solvent Orange 107 and Solvent Yellow 179.

[0177] Examples of the quinophthalone dye include color index dyes such as Solvent Yellow 33, Disperse Yellow 54, and Disperse Yellow 160.

[0178] The thermoplastic resin composition of the molded body (2) of the present invention contains a methacrylic resin and at least one light absorber (B) as a light absorber (L). The content thereof (the total amount when two or more light absorbers are used in combination) can be set to 0.1 to 0.5 parts by mass, preferably 0.15 to 0.35 parts by mass, relative to 100 parts by mass of the methacrylic resin. When the content of the light absorber (B) is above the lower limit, the color selectivity of the transmitted light of the molded body is excellent. When it is below the upper limit, the transmitted light intensity of the molded body is excellent.

[0179] The light absorber (L) of the present invention contains two or more light absorbers having wavelengths different from each other at which absorbance exhibits a maximum value in the wavelength range of 380 nm to 730 nm.

[0180] The number n, which is the number of types of the light absorber (L), is an integer greater than or equal to 2. It is preferably an integer greater than or equal to 2 and less than or equal to 20, more preferably an integer greater than or equal to 2 and less than or equal to 10, further preferably an integer greater than or equal to 2 and less than or equal to 5, and particularly preferably an integer greater than or equal to 3 and less than or equal to 4 from the viewpoint of excellent selectivity of the wavelength of transmitted light.

[0181] As one embodiment of the light absorber (L) of the present invention, the light absorber (L) may include one light absorber (A) and one or more light absorbers (B). As another embodiment of the light absorber (L) of the present invention, the light absorber (L) may not include the light absorber (A) but include one or more light absorbers (B).

[0182] The light absorber (L) in the present invention preferably satisfies either of the following conditions 1 or 2. By satisfying either of the following conditions 1 or 2, the obtained molded article has an excellent jet black color when the light source is off and can exhibit a specific color tone when the light source is on.

[0183] Condition 1:

[0184] There is only one i that satisfies the following formula (5), and satisfies the following formula (6).

[0185] Formula (5):

[0186] λ(i+1)-λ(i)≥160nm···(5)

[0187] Formula (6):

[0188] λ(1)-380nm<160nm···(6)

[0189] Condition 2:

[0190] The following formula (5) is not satisfied, but the following formula (7) is satisfied.

[0191] Formula (5):

[0192] λ(i+1)-λ(i)≥160nm···(5)

[0193] Formula (7):

[0194] λ(1)-380nm≥160nm···(7)

[0195] Note that λ(i) is a wavelength at which the absorbance of the light absorber (i) which is one of the light absorbers (L) shows a maximum value in the wavelength range of 380 nm to 730 nm.

[0196] i is an integer from 1 to n;

[0197] n is an integer greater than or equal to 2, and represents the number of types of the light absorber (L) contained in the molded article or the thermoplastic resin composition;

[0198] λ(n+1) is 730nm;

[0199] λ(1)<λ(2)<···<λ(n)<λ(n+1).

[0200] For example, in the molded product of Example 1 described later, since it contains a light absorber (B1) having a wavelength of 690 nm at which the absorbance shows a maximum value, and a light absorber (A1) having a wavelength of 450 nm at which the absorbance shows a maximum value, n is 2, λ(1) is 450 nm, λ(2) is 690 nm, and λ(3) is 730 nm.

[0201] Substituting this into equation (5), only λ(2)-λ(1) satisfies equation (5) and also satisfies equation (6).

[0202] This result shows that if Figure 2 As shown, only light with a wavelength between λ(1) and λ(2), that is, between 450 nm and 690 nm, is selectively transmitted.

[0203] For example, in the molded body of Example 2 described later, since it contains a light absorber (B1) having a wavelength of 690 nm at which the absorbance shows a maximum value, and a light absorber (A2) having a wavelength of 590 nm at which the absorbance shows a maximum value, n is 2, λ(1) is 590 nm, λ(2) is 690 nm, and λ(3) is 730 nm.

[0204] Substituting this into the formula (5), there is no light absorber (i) satisfying the formula (5), and the formula (7) is satisfied.

[0205] This result shows that if Figure 3 As shown, only light with a wavelength between 380 nm and λ(1), that is, between 380 nm and 590 nm, is selectively transmitted.

[0206] For example, in the molded body of Example 3 described later, since it contains a light absorber (B1) having a wavelength of 690 nm at which the absorbance shows a maximum value, and a light absorber (A3) having a wavelength of 480 nm at which the absorbance shows a maximum value, n is 2, λ(1) is 480 nm, λ(2) is 690 nm, and λ(3) is 730 nm.

[0207] Substituting this into equation (5), only λ(2)-λ(1) satisfies equation (5) and also satisfies equation (6).

[0208] This result shows that if Figure 4 As shown, only light with a wavelength between λ(1) and λ(2), that is, between 480 nm and 690 nm, is selectively transmitted.

[0209] For example, in the molded body of Example 4 described later, since it contains a light absorber (B1) having a maximum absorbance at a wavelength of 690 nm, a light absorber (A4) having a maximum absorbance at a wavelength of 510 nm, and a light absorber (A3) having a maximum absorbance at a wavelength of 480 nm, n is 3, λ(1) is 480 nm, λ(2) is 510 nm, λ(3) is 690 nm, and λ(4) is 730 nm.

[0210] Substituting this into equation (5), only λ(3)-λ(2) satisfies equation (5) and also satisfies equation (6).

[0211] This result shows that if Figure 5 As shown, only light with a wavelength between λ(2) and λ(3), that is, between 510 nm and 690 nm, is selectively transmitted.

[0212] Thus, in the molded article of the present invention, when the wavelengths at which the absorbances of two or more light absorbers that are different from each other in the wavelength range of 380 nm to 730 nm are arranged in ascending order, the difference between any adjacent wavelengths, or only one of λ(1)-380 nm or 730 nm-λ(n), is 160 nm or more in the wavelength range of 380 nm to 730 nm. Therefore, the molded article of the present invention can selectively transmit only light of wavelengths between the wavelengths in the region, and thus, light emitted from a light source (LED) of a specific emission wavelength or white light emitted from a white light source can be transmitted through the molded article, thereby making the light transmitted through the molded article colored light, that is, light of a specific wavelength can be selectively transmitted to present a specific color tone.

[0213] As one embodiment, the light absorber (L) of the present invention satisfies condition 1. In this embodiment, since there is only one i that satisfies λ(i+1)-λ(i)≥160nm (Formula (5)), a molded body that can selectively transmit light of wavelengths between λ(i) and λ(i+1) can be obtained.

[0214] As another embodiment, the light absorber (L) in the present invention satisfies condition 2. In this embodiment, since there is no i satisfying λ(i+1)-λ(i)≥160nm (formula (5)), and λ(1)-380nm is greater than 160nm (formula (7)), a molded body that can transmit light of a wavelength between 380nm and λ(1) can be obtained.

[0215] As another embodiment, the light absorber (L) does not contain the light absorber (A), satisfies condition 1, and the only i satisfying formula (5) is n. That is, formula (5') is satisfied, i other than n does not satisfy formula (5), and formula (6) is satisfied.

[0216] λ(n+1)-λ(n)≥160nm···(5')

[0217] In this embodiment, since λ(n+1)-λ(n) is 160 nm or more, a molded body that can selectively transmit light having a wavelength between λ(n) and 730 nm can be obtained.

[0218] In order to obtain a molded article of the present invention with excellent blackness, it is necessary to reduce the total light transmittance of the molded article or the thermoplastic resin composition. In the molded article of the present invention, by using two or more light absorbers (L) having wavelengths different from each other at which the absorbance shows a maximum value in the wavelength range of 380 nm to 730 nm, the total light transmittance of the molded article can be reduced.

[0219] By combining two or more light absorbers (L), the total light transmittance can be reduced, and light of a specific wavelength can be selectively transmitted to present a specific color tone. Specifically, if light with a wavelength of 380nm to 495nm is transmitted, purple to blue is displayed, if light with a wavelength of 495nm to 570nm is transmitted, green is displayed, if light with a wavelength of 570nm to 620nm is transmitted, yellow to orange is displayed, and if light with a wavelength of 620nm to 700nm is transmitted, red is displayed.

[0220] In order to selectively transmit light of a specific wavelength, it is necessary to adjust the combination of light absorbers (L). As described above, when the wavelengths at which the absorbances of two or more light absorbers different from each other in the wavelength range of 380 nm to 730 nm are arranged in ascending order, the combination of light absorbers can be adjusted so that the difference between any adjacent wavelengths of these wavelengths, or only any one of λ(1)-380 nm or 730 nm-λ(n) is 160 nm or more in the wavelength range of 380 nm to 730 nm.

[0221] In addition, the maximum value of the absorbance of the light absorber (B) in the wavelength range of 380 nm to 730 nm is in the range of 630 nm to 700 nm, so that light in the wavelength range of 730 nm or more can be transmitted, and the solar transmittance of the molded article is not impaired. In addition, by setting the transmittance of light at a wavelength of 770 nm to 0.5% or more or 5% or more, the solar transmittance of the molded article of the present invention can be sufficiently increased.

[0222] Therefore, by using a light absorber (L) satisfying condition 2, or a light absorber (L) containing at least one light absorber (A) and satisfying condition 1, a molded product can be obtained in which the wavelength at which the transmittance of light in the wavelength range of 430 nm to 700 nm shows a maximum value is in the range of 430 nm to less than 680 nm.

[0223] In addition, by using a light absorber (L) that does not contain the light absorber (A), satisfies condition 1, and satisfies formula (5') in which i is n in accordance with formula (5), that is, i other than n does not satisfy formula (5), a molded body can be obtained in which the wavelength at which the transmittance of light in the range of wavelengths from 430 nm to 700 nm shows a maximum value is in the range of from 430 nm to less than 680 nm.

[0224] [Method for producing thermoplastic resin composition]

[0225] The thermoplastic resin composition of the molded article (2) of the present invention can be produced by mixing a methacrylic resin and two or more light absorbers (L). As a mixing method, a known method can be adopted, for example, mixing using a mixer such as a Henschel mixer, a screw mixer, a Banbury mixer, a drum mixer, etc., and further using a kneading machine such as a single-screw extruder, a twin-screw extruder, a multi-screw extruder, etc., usually at a melting temperature of 200 to 300° C. for 5 to 60 minutes to produce the thermoplastic resin composition of the present invention.

[0226] The molded article or thermoplastic resin composition of the present invention may contain other additives within the range that does not impair the original performance. Examples of other additives include impact resistance modifiers, ultraviolet absorbers, light stabilizers, antioxidants, and mold release agents.

[0227] The other additives may be used alone or in combination of two or more.

[0228] <Display device>

[0229] The display device of the present invention can adopt a known configuration except that it includes the molded article of the present invention. Figure 1 It is a schematic diagram showing an example of the display device of the present invention.

[0230] The display device 1 of the present invention includes a light source 10 and a molded body 12 of the present invention, wherein the molded body 12 is configured so that light 20 emitted by the light source passes through the molded body. The molded body of the present invention has excellent blackness and can selectively transmit light of a specific wavelength to present a specific color tone. Therefore, even when a white light source is used as the light source 10, the light 22 emitted from the light source and transmitted through the molded body 12 becomes colored light of a specific color tone according to the light transmittance of the molded body 12 of the present invention, so that display based on colored light can be performed.

[0231] Examples of the white light source include an incandescent lamp, a fluorescent lamp, an LED lamp, and a HID lamp.

[0232] The white light source may be used alone or in combination of two or more.

[0233] The light source 10 used in the display device 1 of the present invention may be a light source other than a white light source.

[0234] For example, when it is desired to transmit red light, a display device having excellent red transmitted light intensity can be obtained by combining a known red light emitting diode (red LED) with the molded article of the present invention that transmits red light.

[0235] When it is desired to transmit blue light, a display device having excellent blue transmitted light intensity can be obtained by combining a known blue light emitting diode (blue LED) with the molded article of the present invention that transmits blue light.

[0236] When yellow light or orange light is to be transmitted, a display device having excellent intensity of yellow or orange transmitted light can be obtained by combining a known white light source with the molded article of the present invention that transmits yellow light or orange light.

[0237] The distance between the light source 10 and the molded body 12 is not particularly limited as long as it is a distance at which the color of the light 22 emitted from the light source and transmitted through the molded body 12 can be confirmed by naked eye. Since there is no need to extremely increase the light intensity of the light source, it is preferably greater than 0.1 cm and less than 100 cm, and more preferably greater than 0.1 cm and less than 30 cm.

[0238] Example

[0239] Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples.

[0240] (Materials used in production of thermoplastic resin composition)

[0241] Thermoplastic resin: Methacrylic resin (trade name "ACRYPET (registered trademark) VH", manufactured by Mitsubishi Chemical Corporation)

[0242] Light absorber (A):

[0243] Light absorber (A1): a dye with a color index of Solvent Orange 60, a wavelength at which the absorbance shows a maximum value of 450 nm)

[0244] Light absorber (A2): dye with color index Solvent Violet 13, wavelength at which absorbance shows maximum value 590 nm)

[0245] Light absorber (A3): dye with color index Solvent Red 179, wavelength of maximum absorbance 480nm)

[0246] Light absorber (A4): dye with color index Solvent Red 168, wavelength of maximum absorbance 510 nm)

[0247] Light absorber (A5): a dye with a color index of Solvent Blue 94, a wavelength of 620 nm at which the absorbance shows a maximum value)

[0248] Light absorber (B):

[0249] Light absorber (B1): a dye with a color index of Solvent Green 28, a wavelength at which the absorbance shows a maximum value of 690 nm)

[0250] Other light absorbers (C):

[0251] Light absorber (C1): anthraquinone dye (trade name "SDO-11", manufactured by Arimoto Chemical Industry Co., Ltd., wavelength showing maximum absorbance: 755 nm)

[0252] (Measurement of transmittance)

[0253] Regarding the transmittance of the molded article to light with a wavelength of 380 nm to 780 nm, light with a wavelength of 380 nm to 780 nm was transmitted from the back side of the molded article, and the light transmitted from the surface of the molded article was measured using a spectrophotometer (model "U4100", manufactured by Hitachi High-Technologies Corporation).

[0254] (Determination of L* value)

[0255] The L* value of the reflected light of the molded article was calculated based on the tristimulus values ​​X, Y, and Z measured by reflection measurement using a spectrophotometer (model "U4100", manufactured by Hitachi High-Technologies) under the conditions of C light source and viewing angle of 2° in accordance with ISO 11664-4. It should be noted that the reflection measurement uses an integrating sphere to collect and receive light by accumulating the specular reflection component and the diffuse reflection component.

[0256] (Measurement of total light transmittance)

[0257] The total light transmittance of the molded article was measured in accordance with ISO 13468-1 using a transmittance meter (model "HM-100", manufactured by Murakami Color Research Laboratory Co., Ltd.).

[0258] It should be noted that "0%" shown in Table 2 is a low value exceeding the detection limit, and according to the reading accuracy of the above-mentioned transmittance meter, it is at least 0.1% or less.

[0259] (5) Solar transmittance

[0260] As an index of heat shielding property, solar transmittance was measured according to the following procedure in accordance with JIS R3106. For a test piece of the resin molded body (50 mm in length × 50 mm in width, thickness: 3 mm), the spectral transmittance (unit: %) at a wavelength of 300 to 2100 nm was measured using an ultraviolet-visible-near-infrared spectrophotometer (manufactured by Hitachi High-Tech Science, model: UH4150), and the solar transmittance was calculated based on JIS R3106.

[0261] (Measurement of the color of transmitted light)

[0262] White light (LED lamp, trade name "MAGLITE ST2D") was transmitted through the back side of the molded article, and the color of the light transmitted through the surface of the molded article was confirmed by visual observation.

[0263] [Example 1]

[0264] 100 parts by mass of a thermoplastic resin, 0.18 parts by mass of a light absorber (A1), and 0.18 parts by mass of a light absorber (B1) were mixed using a Henschel mixer (model "SMV-20", manufactured by KAWATA Corporation), and then kneaded at a melt temperature of 250° C. using a twin-screw extruder (model "PCM45", manufactured by Ikegai Co., Ltd.) to obtain pellets of a thermoplastic resin composition.

[0265] The obtained pellets of the thermoplastic resin composition were injection molded using an injection molding machine (model "SAV-60", manufactured by Yamashiro Seiki Co., Ltd.) at a cylinder temperature of 250°C and a mold temperature of 60°C to obtain a flat plate molded body (size: 100 mm×50 mm, thickness 2 mm).

[0266] Table 2 shows the evaluation results of the obtained molded products.

[0267] The transmittance of the obtained molded body to light with a wavelength of 380 nm or more and 780 nm or less is shown in FIG. Figure 2 .

[0268] [Examples 2 to 5, Comparative Examples 1 to 3]

[0269] A molded product was obtained in the same manner as in Example 1 except that the light absorber used was changed as shown in Table 1. In addition, the numbers in the table represent the content (parts by mass).

[0270] Table 2 shows the evaluation results of the obtained molded products.

[0271] The transmittances of the molded bodies obtained in Examples 2 to 5 and Comparative Examples 1 to 3 for light having a wavelength of 380 nm or more and 780 nm or less are shown in FIG. Figures 3 to 9 .

[0272] [Table 1]

[0273]

[0274]

[0275] [Table 3]

[0276]

[0277] The molded bodies obtained in Examples 1 to 5 have high solar transmittance, excellent blackness when the light source is off, and excellent blackness when the light source is on. Figures 2 to 5 and Fig. 9 It is shown that it is possible to selectively transmit light of a specific wavelength to present a specific hue.

[0278] The molded bodies obtained in Comparative Examples 1 to 3 have excellent blackness, as shown in FIG. Figures 6 to 8 It can selectively transmit light of a specific wavelength and present a specific color tone, but the sunlight transmittance is low.

[0279] Industrial Applicability

[0280] The molded body of the present invention has excellent blackness when the light source is off, and can selectively transmit light of a specific wavelength when the light source is on, presenting a specific color tone. Moreover, the sunlight transmittance is high. Therefore, it is not easy to store heat, and it is not easy to deform, denature, or thermal crack due to heat. Therefore, it can be suitably used in display devices that display text, numbers, signals, etc.; vehicle exterior products such as pillars, decorative parts, front grilles, bumpers, decorative strips; appearance components that require a high-end appearance, etc., and can be particularly suitably used in display devices.

Claims

1. A molded body comprising a transparent resin, The L* value of reflected light of the molded article is 35 or less, and In the wavelength range of 430 nm to 700 nm, the wavelength at which the light transmittance shows a maximum value is in the range of 430 nm to less than 680 nm. The maximum value of the light transmittance at the wavelength at which the light transmittance shows a maximum value in the wavelength range of 430 nm to 700 nm is 0.1% or more, The molded article contains two or more light absorbers (L), and the two or more light absorbers (L) have different wavelengths at which absorbances show maximum values ​​in the wavelength range of 380 nm to 730 nm. The light absorber (L) includes a light absorber (B) having a wavelength at which the absorbance shows a maximum value within a range of 630 nm to 700 nm, The light absorber (L) does not contain a light absorber having a wavelength exceeding 720 nm at which the absorbance shows a maximum value. The molded body has a light transmittance of 0.5% or more at a wavelength of 770 nm.

2. The molded article according to claim 1, which has a total light transmittance of less than 5%.

3. The molded article according to claim 1, wherein The transmittance of light at a wavelength of 770 nm is 1% or more.

4. The molded article according to claim 1, wherein The transparent resin is methacrylic resin.

5. A molded article obtained by molding a thermoplastic resin composition, the thermoplastic resin composition comprising a methacrylic resin and two or more light absorbers (L), wherein the two or more light absorbers (L) have different wavelengths at which absorbances show maximum values ​​in a wavelength range of 380 nm to 730 nm, wherein: The light absorber (L) includes a light absorber (B) having a wavelength at which the absorbance shows a maximum value within a range of 630 nm to 700 nm, The light absorber (L) does not contain a light absorber having a wavelength exceeding 720 nm at which the absorbance shows a maximum value. The L* value of the reflected light of the molded body is 35 or less, The total light transmittance is less than 1%, In the wavelength range of 430 nm to 700 nm, the wavelength at which the light transmittance shows a maximum value is in the range of 430 nm to less than 680 nm. The maximum value of the light transmittance at the wavelength at which the light transmittance shows a maximum value in the wavelength range of 430 nm to 700 nm is 0.1% or more, The molded body has a light transmittance of 5% or more at a wavelength of 770 nm.

6. The molded article according to claim 5, wherein The light absorber (B) includes a light absorber selected from anthraquinone dyes, pyrene dyes, methine dyes, and quinophthalone dyes.

7. The molded article according to claim 5, wherein The total content of the light absorber (B) is 0.1 part by mass or more and 0.5 part by mass or less based on 100 parts by mass of the methacrylic resin.

8. The molded article according to claim 1 or 5, wherein The light absorber (L) satisfies any one of the following conditions 1 or 2, Condition 1: There is only one i that satisfies the following formula (5) and satisfies the following formula (6), Formula (5): λ(i+1)-λ(i)≥160nm···(5) Formula (6): λ(1)-380nm<160nm···(6) Condition 2: Does not satisfy the following formula (5), but satisfies the following formula (7), Formula (5): λ(i+1)-λ(i)≥160nm···(5) Formula (7): λ(1)-380nm≥160nm···(7) In the formula, λ(i) is the wavelength at which the absorbance of the light absorber (i) as one of the light absorbers (L) shows a maximum value in the wavelength range of not less than 380 nm and not more than 730 nm, i is an integer from 1 to n, n is an integer not less than 2 and represents the number of types of the light absorber (L), λ(n+1) is 730 nm, λ(1)<λ(2)<···<λ(n)<λ(n+1). 9 . The molded article according to claim 1 , comprising, as the light absorber (L), a light absorber (A) having a wavelength at which absorbance shows a maximum value in a range of 400 nm to less than 630 nm.

10. The molded article according to claim 4 or 5, comprising, as the light absorber (L), a light absorber (A) having a wavelength at which absorbance exhibits a maximum value in the range of 400 nm or more and less than 630 nm, The total content of the light absorber (A) is 0.001 parts by mass or more and 1 part by mass or less relative to 100 parts by mass of the methacrylic resin.

11. The molded article according to claim 9, wherein The light absorber (A) includes a light absorber selected from anthraquinone pigments and phthalocyanine pigments.

12. A display device, comprising: Light source, and The molded article according to any one of claims 1 to 11, wherein The molded body is arranged so that light emitted from the light source transmits through the molded body.

Images