Polycarbonate resin composition and optical molded article composed thereof

Abstract

Provided are a polycarbonate resin composition comprising a polycarbonate resin, a black colorant, a yellow colorant, and at least one ultraviolet absorber selected from the group consisting of a benzotriazole-based compound, a benzophenone-based compound, and a triazine-based compound, and an optical molded article composed thereof.

Claims

1. A polycarbonate resin composition comprising a polycarbonate resin, a black colorant, a yellow colorant, and at least one ultraviolet absorber selected from the group consisting of a benzotriazole-based compound, a benzophenone-based compound, and a triazine-based compound, wherein: an average transmittance in a wavelength region of 380 nm to 420 nm is 1.0% to 6.5%, as measured in accordance with ASTM D1003; the yellow colorant is present in an amount from 0.5 ppmw to 5.0 ppmw with respect to the total dry weight of the composition; the benzotriazole-based compound is a compound of the following Chemical Formula 1: ##STR00011## the benzophenone-based compound is a compound of the following Chemical Formula 2: ##STR00012## and the triazine-based compound is a compound of the following Chemical Formula 3: ##STR00013##

2. The polycarbonate resin composition of claim 1, wherein at least one ultraviolet absorber is the benzotriazole-based compound of Chemical Formula 1.

3. The polycarbonate resin composition of claim 1, wherein at least one ultraviolet absorber is the benzophenone-based compound of Chemical Formula 2.

4. The polycarbonate resin composition of claim 1, wherein at least one ultraviolet absorber is the triazine-based compound of Chemical Formula 3.

5. The polycarbonate resin composition of claim 1, wherein the black colorant is selected from the group consisting of an anthraquinone-based compound, an azophenyl-based compound, an acetamide-based compound, and a carbon-based compound.

6. The polycarbonate resin composition of claim 1, wherein the yellow colorant is selected from the group consisting of a quinoline-based compound, a pyrazole-based compound, and a naphthalene-based compound.

7. The polycarbonate resin composition of claim 1, wherein the ultraviolet absorber is present in an amount from 1000 ppmw to 15,000 ppmw with respect to the total dry weight of the composition.

8. The polycarbonate resin composition of claim 1, wherein the black colorant is present in an amount from 1.0 ppmw to 10.0 ppmw with respect to the total dry weight of the composition.

9. The polycarbonate resin composition of claim 1, wherein the polycarbonate resin includes a repeating unit of the following Chemical Formula 4: ##STR00014## wherein in Chemical Formula 4: R′.sub.1 to R′.sub.4 are each independently hydrogen, a C.sub.1-10 alkyl, a C.sub.1-10 alkoxy, or a halogen; and Z′ is a C.sub.1-10 alkylene unsubstituted or substituted with a phenyl, a C.sub.3-15 cycloalkylene unsubstituted or substituted with a C.sub.1-10 alkyl, O, S, SO, SO.sub.2, or CO.

10. The polycarbonate resin composition of claim 9, wherein the repeating unit of Chemical Formula 4 is derived from any one or more aromatic diol compounds selected from the group consisting of bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)ether, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)ketone, 1,1-bis(4-hydroxyphenyl)ethane, bisphenol A, 2,2-bis(4-hydroxyphenyl)butane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane, 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane, 2,2-bis(4-hydroxy-3-bromophenyl)propane, 2,2-bis(4-hydroxy-3-chlorophenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, and bis(4-hydroxyphenyl)diphenylmethane.

11. The polycarbonate resin composition of claim 1, wherein the polycarbonate resin has a weight average molecular weight of 1000 g/mol to 100,000 g/mol.

12. The polycarbonate resin composition of claim 1, further comprising at least one additive selected from the group consisting of an antioxidant, a heat stabilizer, a plasticizer, an antistatic agent, a nucleating agent, a flame retardant, a lubricant, an impact modifier, and a fluorescent brightener.

13. An optical molded article, comprising the polycarbonate resin composition of claim 1.

Description

BRIEF DESCRIPTION OF DRAWING

(1) FIGS. 1A-1C are images showing appearance evaluation criteria of examples and comparative examples.

EXAMPLES

(2) Hereinafter, preferred embodiments will be provided for better understanding of the present invention. However, the following embodiments are for illustrative purposes only, and the present invention is not intended to be limited thereby.

(3) Materials Used

(4) The following materials were used in the examples and comparative examples.

(5) 1) (A) Polycarbonate [PC]

(6) Bisphenol A linear polycarbonate resin (A-1) having a weight average molecular weight of 31,000 g/mol and MFR (300° C., 1.2 kg) of 9.5 g/min was used.

(7) 2) (B) colorant

(8) B-1: black colorant, Nubian Black PC-0870 manufactured by Orient Chemical

(9) B-2: yellow colorant, Transparent Yellow 3G manufactured by Yabang

(10) B-3: red colorant, MACROLEX Red E2G manufactured by Lanxess

(11) 2) (C) ultraviolet absorber

(12) C-1: a compound of Chemical Formula 1 (TINUVIN 326)

(13) ##STR00006##

(14) C-2: a compound of Chemical Formula 2 (UVINUL 3049)

(15) ##STR00007##

(16) C-3: a compound of Chemical Formula 3 (LA-F70)

(17) ##STR00008##

(18) C-4: a compound of Chemical Formula 5 (TINUVIN 360)

(19) ##STR00009##

(20) C-5: a compound of Chemical Formula 6 (TINUVIN 329)

(21) ##STR00010##

Examples and Comparative Examples

(22) The respective components were mixed in a content as described in Table 1 below, and pellets were produced at a rate of 80 kg per hour with a twin-screw extruder (L/D=36, Φ=45, barrel temperature: 240° C.).

(23) In Table 1, the content of the polycarbonate resin (A) refers to an amount excluding the contents of the remaining colorant (B) and ultraviolet absorber (C) from a total of 100 wt % of the composition.

(24) TABLE-US-00001 TABLE 1 Polycarbonate resin (A) (type/content Colorant (B) Section (wt %)) (type/content (ppmw)) Ultraviolet absorber (C) (type/content (ppmw)) Example 1 A-1/balance B-1/5 B-2/1 — C-1/6000 — — Example 2 A-1/balance B-1/5 B-2/1 — — C-2/6000 Example 3 A-1/balance B-1/5 B-2/1 — — — C-3/6000 Example 4 A-1/balance B-1/3 B-2/3 — C-1/6000 Example 5 A-1/balance B-1/1 B-2/5 — C-1/6000 Example 6 A-1/balance B-1/5 B-2/1 — — C-2/8000 Example 7 A-1/balance B-1/5 B-2/1 — — — C-3/10000 Comparative A-1/balance — — — C-4/6000 Example 1 Comparative A-1/balance — — — C-4/8000 Example 2 Comparative A-1/balance B-1/5 B-2/1 — C-4/6000 Example 3 Comparative A-1/balance — — — C-5/6000 Example 4 Comparative A-1/balance B-1/5 B-2/1 C-5/6000 Example 5 Comparative A-1/balance — — — C-1/6000 — — Example 6 Comparative A-1/balance — — — C-1/8000 — Example 7 Comparative A-1/balance — — — — C-2/6000 Example 8 Comparative A-1/balance — — — — — C-3/6000 Example 9 Comparative A-1/balance B-1/6 — — C-1/6000 — — Example 10 Comparative A-1/balance — B-2/6 — C-1/6000 — — Example 11 Comparative A-1/balance — — B-3/6 C-1/6000 — — Example 12

(25) Experimental Method

(26) (1) Experimental Example 1: Transmittance (T), 420 nm Transmittance (T.sub.420), and 380-420 nm Average Transmittance (T.sub.380-420)

(27) The respective resin pellets prepared in the examples and comparative examples were injection-molded without residence time at a cylinder temperature of 320° C. using an injection molding machine N-20C (manufactured by JSW, Ltd.) to prepare a specimen (width/length/thickness=60 mm/40 mm/3 mm), while transmittance (T) was measured using ULTRASCAN PRO equipment (manufactured by HunterLab) (instrument setting: 360 nm to 750 nm) in accordance with ASTM D1003, and the results are shown in the following Table 2.

(28) Further, transmittance (T.sub.420) at 420 nm was measured, and transmittances from 380 nm to 420 nm were also measured at 5 nm wavelength intervals, and an average value thereof (T.sub.380-420) is shown in the following Table 2.

(29) (2) Experimental Example 2: Evaluation of Color Stability

(30) The color stability was evaluated by combining the following evaluation results of yellowness index and appearance. Higher YI values negatively influence deterioration of color stability, but resins with a YI value of up to about 20 can be applied to products. However, even if the YI value is 20 or less, color stability is considered to be lowered, when a yellow color is observed with the naked eye.

(31) (2-1) Evaluation of Yellowness Index (YI)

(32) The respective resin pellets prepared in the examples and comparative examples were injection-molded without residence time at a cylinder temperature of 270° C. using an injection molding machine N-20C (manufactured by JSW, Ltd.) to prepare a specimen (width/length/thickness=60 mm/40 mm/3 mm), while YI values were measured using ULTRASCAN PRO equipment (manufactured by HunterLab) in accordance with ASTM D1925, and the results are shown in the following Table 2.

(33) (2-2) Evaluation of Appearance

(34) The respective resin pellets prepared in the examples and comparative examples were injection-molded without residence time at a cylinder temperature of 270° C. using an injection molding machine N-20C (manufactured by JSW, Ltd.) to prepare a specimen (width/length/thickness=60 mm/40 mm/3 mm), and yellowness of the specimen was observed with the naked eye. ○, Δ, and X were determined by relative evaluation between the subject specimens.

(35) <Appearance Evaluation Criteria>

(36) ○: The sample shows almost no yellow color, which is similar to the sample specimen image of FIG. 1A.

(37) Δ: The sample shows a light yellow color, which is similar to the sample specimen image of FIG. 1B.

(38) X: The sample shows a dark yellowcolor, which is similar to the sample specimen image of FIG. 1C.

(39) TABLE-US-00002 TABLE 2 Average Transmit- Transmit- Appear- Transmit- tance tance at ance tance at 420 nm 380 nm-420 nm evalua- Section YI (T) % (T.sub.420), % (T.sub.380-420), % tion Example 1 10.2 88.1 24.8 6.2 ◯ Example 2 15.1 87.9 24.5 6.0 ◯ Example 3 15.2 87.8 23.4 5.8 ◯ Example 4 13.4 88.4 24.3 6.0 ◯ Example 5 15.5 88.2 22.5 5.6 ◯ Example 6 18.8 86.9 19.5 4.8 ◯ Example 7 20.1 86.1 15.2 3.7 ◯ Comparative 6.8 89.2 52.2 12.5 X Example 1 Comparative 10.2 87.8 43.4 10.6 X Example 2 Comparative 7.7 86.9 42.2 10.4 ◯ Example 3 Comparative 6.5 89.5 48.8 12 X Example 4 Comparative 7.5 87.5 41.2 10 ◯ Example 5 Comparative 7.3 89.9 31.8 7.8 X Example 6 Comparative 15.9 88.9 29.1 7.1 X Example 7 Comparative 13.5 89.6 28.9 7.1 X Example 8 Comparative 13.9 89.4 28.2 7.0 X Example 9 Comparative 7.5 87.4 27.6 7.0 ◯ Example 10 Comparative 18.2 88.4 22.2 6.0 X Example 11 Comparative 6.0 88.6 32.3 7.9 Δ Example 12

(40) As shown in Table 2, examples of the present invention were confirmed to have excellent transparency and low UV transmittance at 420 nm at the same time by using the additive having high light absorption in a specific wavelength region and a combination of the specific colorants. Further, when the samples were observed with the naked eye, they showed almost no yellow color, and their YI values were 20 or less, indicating excellent color stability.

(41) Comparative examples not using the ultraviolet absorber and colorants showed very high 380 nm-420 nm average transmittance, and most of the samples showed a dark yellow color. In particular, it was confirmed that Comparative Examples 1 to 5 using different materials which are conventionally used as ultraviolet absorbers showed overall excellent average transmittance, but remarkably high transmittance at 420 nm, as compared with the examples.

(42) It was confirmed that Comparative Example 11 showed 380 nm-420 nm average transmittance equivalent to those of the examples, but its application to products was not easy because it showed a dark yellow color when observed with the naked eye.