Carbon black and application thereof

Abstract

To provide a carbon black with high dispersibility.SOLUTION: The present invention provides carbon black, having a full width at half maximum (FWHM) of greater than 0 and less than or equal to 0.3 μm as measured by a centrifugal sedimentation process, wherein the centrifugal sedimentation process uses anhydrous ethanol as a solvent.SELECTED DRAWING: None

Description

[Technical field]

[0001] This application claims priority to Taiwan Patent Application No. 112132586, filed on August 29, 2023, the entire text of which is incorporated by reference herein.

[0002] This disclosure relates to carbon blacks, and in particular to carbon blacks suitable for use in coatings. [Background technology]

[0003] Carbon black is a type of amorphous carbon, which is widely used in industry as a colorant and filler. When used as a colorant, it can give inks and paints a black or darker color. When used as a filler, it can improve the mechanical strength of rubber products. Carbon black is widely used in various fields because it can not only color products, but also enhance the mechanical properties of products.

[0004] However, in practical applications, the carbon black content in the product is usually not that high, because when the carbon black content exceeds a critical value, the mechanical strength of the product is reduced. Therefore, it is generally desired in the industry to make the blackness of the carbon black as high as possible so that a smaller amount of carbon black can be used to achieve the desired blackness of the product. Summary of the Invention [Problem to be solved by the invention]

[0005] In view of the above problems, an object of the present disclosure is to provide a carbon black that can impart high blackness to a product by adding it to the product. [Means for solving the problem]

[0006] In order to achieve the above object, the present disclosure provides a carbon black having a full width at half maximum (FWHM) greater than 0 and equal to or less than 0.3 μm as measured by a centrifugal sedimentation method, the centrifugal sedimentation method using anhydrous ethanol as a solvent.

[0007] Preferably, the full width at half maximum is greater than 0 and equal to or less than 0.2 μm. More preferably, the full width at half maximum is greater than 0 and equal to or less than 0.17 μm.

[0008] Preferably, the carbon black has a modal particle size greater than 0 and less than 0.4 μm as measured by centrifugal sedimentation using absolute ethanol as a solvent, and more preferably, the modal particle size is greater than 0 and less than 0.3 μm.

[0009] Preferably, the primary particle size is 10 to 80 nm.

[0010] Preferably, the carbon black is in the form of aggregates having a particle size of 100 to 600 nm.

[0011] Preferably, the carbon black has a volatile content of 2% to 10% by weight.

[0012] Preferably, the carbon black has a tinting strength of 90% to 128%.

[0013] The present disclosure also provides uses of the carbon black, wherein the carbon black is used in coatings.

[0014] Preferably, the coating is an ink, a metallic paint, or a color paste. Effect of the Invention

[0015] The carbon black of the present disclosure has good dispersibility and, when added to a product, can impart a high blackness to the product. [Brief description of the drawings]

[0016] [Figure 1A] 1 shows a particle size distribution curve of the carbon black of Production Example 1. [Figure 1B] 1 shows a particle size distribution curve of the carbon black of Production Example 2. [Figure 1C] 1 shows a particle size distribution curve of the carbon black of Comparative Example 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Detailed Description of the Embodiments As used herein, "full width at half maximum (FWHM)" refers to the width at half height of the particle size distribution curve.

[0018] In this disclosure, the "mode particle size (D mode )" refers to the diameter determined by the maximum peak of the particle size distribution curve.

[0019] In this disclosure, the "particle size distribution curve" is obtained by centrifugal sedimentation, which uses absolute ethanol as the solvent.

[0020] In this disclosure, "between X and Y" is synonymous with "from X to Y" and includes the extreme values ​​X and Y.

[0021] The carbon black provided by the present disclosure has a full width at half maximum (FWHM) measured by centrifugal sedimentation method that is greater than 0 and less than or equal to 0.3 μm. In some embodiments, the full width at half maximum is between any two values ​​(between X and Y above) of 0.3, 0.27, 0.25, 0.23, 0.21, 0.2, 0.19, 0.17, 0.16, 0.13, 0.1, 0.07, 0.05, 0.03, and 0.01 μm. In some embodiments, the full width at half maximum is greater than 0 and less than or equal to 0.2 μm. In some embodiments, the full width at half maximum is greater than 0 and less than or equal to 0.17 μm.

[0022] The modal particle size of the carbon black as measured by centrifugal sedimentation may be greater than 0 and less than or equal to 0.4 μm. In some embodiments, the modal particle size is between any two of 0.4, 0.37, 0.35, 0.33, 0.31, 0.29, 0.28, 0.27, 0.26, 0.25, 0.24, 0.23, 0.22, 0.21, 0.17, 0.15, 0.13, 0.1, 0.08, 0.06, 0.049, 0.04, 0.288, 0.02, and 0.01 μm. In some embodiments, the modal particle size is greater than 0 and less than or equal to 0.3 μm. In some embodiments, the modal particle size is greater than 0 and less than or equal to 0.2 μm.

[0023] In some embodiments, the primary particle size of the carbon black is between 10 and 80 nm. In some embodiments, the primary particle size of the carbon black is between any two of 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, and 75 nm. In some embodiments, the particle size of the carbon black aggregate is between 100 and 600 nm. In some embodiments, the particle size of the carbon black aggregate is between any two of 125, 150, 175, 200, 225, 250, 275, 300, 325, 350, 375, 400, 425, 450, 475, 500, 525, 550, and 575 nm.

[0024] The volatile content of the carbon black may be between 2% and 10% by weight. In some embodiments, the volatile content is between any two of 2.2%, 2.4%, 2.6%, 2.8%, 3.5%, 4.0%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, and 9.5% by weight.

[0025] In the present disclosure, the tint strength of the carbon black can be between 90% and 128%. In some embodiments, the tint strength is between any two of 91%, 95%, 97%, 100%, 102%, 107%, 110%, 112%, 115%, 117%, 120%, 123%, 125%, and 127%.

[0026] The present disclosure also provides the use of the carbon black for use in a coating, including but not limited to an ink, a metallic paint, or a color paste. The color paste may be a polyurethane (PU) color paste.

[0027] [Manufacturing example: Carbon black manufacturing] The carbon blacks of Preparation Examples 1 and 2 were prepared by modifying JE4205 carbon black from International China Rubber Co., Ltd. using the carbon material post-modification processing system disclosed in Taiwan Patent No. I796678. The preparation conditions are shown in Table 1. The contents of Taiwan Patent No. I796678 are incorporated herein by reference in their entirety.

[0028] [Table 1]

[0029] Table 2 shows the nitrogen adsorption specific surface area (NSA), oil absorption (OAN), tinting strength (Tint) and volatile matter content of the carbon blacks of Production Example 1, Production Example 2 and Comparative Example 1. The carbon black of Comparative Example 1 in Table 2 refers to unmodified JE4205 carbon black. The measurement items listed in Table 2 are performed as follows.

[0030] [NSA (Nitrogen Adsorption Specific Surface Area)] The specific surface area of ​​carbon black is measured according to ASTM D6556. The gas pressure of the gas adsorbed and desorbed on the surface and pores of carbon black at a constant temperature is measured according to the BET theory, using the nitrogen surface area as the total surface area of ​​the external and internal surfaces. The specific surface area is calculated using the cross-sectional area of ​​the gas molecule, the volume of the gas molecule and the sample weight.

number

[0031] [OAN (oil absorption number)] The OAN of carbon black is measured according to ASTM D2414. A quantitative amount of carbon black is weighed and the density is 1.042-1.047g / cm 3 Titrate to the end point with 100% white mineral oil. Calculate the absorbency value based on the weight of the carbon black sample and the titration volume, then substitute into the following equation to obtain the OAN value:

number

[0032] [Coloring power] The tinting strength of carbon black is measured according to ASTM D3265. After weighing out a certain amount of carbon black, zinc oxide, and epoxidized soybean oil, grinding and dispersing them, a film puller is used to pull out an ink paste film with a length of 7 mm and a width of 4 mm. A black meter is used to measure the reflectance of the ink paste. The tinting strength is calculated according to the following formula: T in the following formula represents tinting strength.

number

[0033] [Volatile content] The amount of organic compounds released by baking carbon black at 950°C for 7 minutes, such as residual oil, adhesives, and surface functional groups, can be measured, and the loss rate can be calculated by measuring the weight of the crucible before and after baking the carbon black.

[0034] [Table 2]

[0035] 1A, 1B, and 1C show the particle size distribution curves of carbon blacks of Production Example 1, Production Example 2, and Comparative Example 1, respectively. The particle size distribution curves of the aggregates were measured by centrifugal sedimentation using anhydrous ethanol as a solvent without using a dispersant. The particle size distribution curves were measured using a Brookhaven Instrument BI-DCP disc centrifuge equipped with a red light diode, and the distribution curves of the aggregates of the dispersed solids were determined based on absorbance measurements. The detailed measurement method is described below.

[0036] 2 g of carbon black and 25 ml of anhydrous ethanol were placed in a 50 ml beaker, and the beaker containing the carbon black slurry was placed in an ultrasonic vibration water bath. It was pre-dispersed by shaking for 1 minute. Next, a probe vibrator was placed in the slurry cooled with ice outside the beaker, and it was dispersed under ultrasonic vibration (70% pulse) for 5 minutes to obtain a carbon black dispersion.

[0037] Before starting the measurement, the centrifuge is run at 8000 rpm for 10 min. Then, 1 ml of absolute ethanol and 15 ml of deionized water are injected sequentially as the spin solution, and 200 μl of n-dodecane is used to cover the spin solution in the centrifuge. Then, 0.2 ml of the dispersion along with the spin solution is injected into the turntable to start the measurement program, and the original data is used for the instrument's calculation processing under astigmatism correction and automatic baseline correction to obtain the results shown in Figure 1A, Figure 1B, Figure 1C and Table 3.

[0038] [Table 3]

[0039] [Example] [Metallic paint manufacturing] The components listed in Table 4 are mixed in the proportions, and the carbon black is the carbon black of Production Example 1, Production Example 2, or Comparative Example 1. After mixing, the mixture is mixed uniformly using a high-speed mixer, and the resulting slurry is placed in a horizontal bead mill and ground for 50 minutes. After grinding, the fineness is measured using a fineness gauge until the fineness is less than 10 μm. Then, a solvent is added to adjust the viscosity to the same range (i.e., the viscosity is FC#4 60±10 seconds) to obtain the metallic paints of Example 1 (metallic paint containing the carbon black of Production Example 1), Example 2 (metallic paint containing the carbon black of Production Example 2), and Comparative Example 2 (metallic paint containing the carbon black of Comparative Example 1).

[0040] [Table 4] <Note> In the above table, BCS / Xylene / #150=40 / 40 / 20 is used as diluent, where #150 refers to Paint Solvent-150 (Highly Flammable Aromatic Naphtha-150), and BYK-118, BYK057, and POLYFLOW No.90 are used as additives.

[0041] The metallic paints of Example 1, Example 2 and Comparative Example 2 were coated on a tinplate with a wire bar and baked at 130°C for 30 minutes. Then, the gloss was measured with a glossmeter (Dr Lange REFO3) and the blackness and hue were measured with a colorimeter (X-rite Ci7600). When measuring the blackness and hue, the SCE* (specular reflection removed) mode was used to remove the specular reflection and faithfully reproduce the color as seen by the human eye. The test results are shown in Table 5.

[0042] [Table 5]

[0043] As shown in Table 5, the metallic paint containing the (modified) carbon black of the present disclosure has excellent blackness (i.e., L * As shown in Table 2, the carbon black of Production Example 1 and Production Example 2 have a certain degree of blackness, but it is noteworthy that the blackness is significantly lower than that of the carbon black of Comparative Example 1 (i.e., the tinting power is significantly lower than that of the carbon black of Comparative Example 1). However, the experimental results in Table 5 show that the metallic paint produced using the carbon black of Production Example 1 or 2 has a higher blackness than the metallic paint produced using Comparative Example 1. This result proves that the carbon black of Production Example 1 or 2 has extremely excellent dispersibility in the metallic paint. Therefore, the essence of carbon black can be fully reproduced in the metallic paint, and the metallic paint can have excellent blackness.

[0044] [Manufacture of PU color paste] The components listed in Table 6 were mixed in a certain ratio to prepare PU color paste precursors of Example 3 and Example 4 using carbon black of Preparation Example 1 and Preparation Example 2, respectively.

[0045] [Table 6]

[0046] Add 18g of #150 solvent to the PU color paste precursor of Example 3 and Example 4 and stir for 10 minutes. Measure the viscosity (centipoise, cps) and torque % value with BROOKFIELD equipment. The results are shown in Table 7.

[0047] [Table 7]

[0048] The results in Table 7 show that the PU color paste precursors of Examples 3 and 4 have good fluidity, and the carbon black of Production Examples 1 and 2 can be well dispersed in the PU color paste.

[0049] In summary, it can be seen that the carbon black of the present disclosure can impart not only high gloss to a coating, but also excellent blackness to the coating, and that the carbon black of the present disclosure has good dispersibility in the coating and excellent dispersion performance.

[0050] However, the above are merely preferred embodiments of the present disclosure and cannot be used to limit the scope of the present disclosure, i.e., all simple equivalent changes and modifications made based on the claims and specifications of the present disclosure are included within the scope of the claimed disclosure.

[0051] (Additional Note) (Appendix 1) A carbon black having a full width at half maximum (FWHM) greater than 0 and less than 0.3 μm as measured by a centrifugal sedimentation method, the centrifugal sedimentation method using anhydrous ethanol as a solvent.

[0052] (Appendix 2) 2. The carbon black according to claim 1, having a full width at half maximum of greater than 0 and less than or equal to 0.2 μm.

[0053] (Appendix 3) 3. The carbon black according to claim 2, having a full width at half maximum of greater than 0 and less than or equal to 0.17 μm.

[0054] (Appendix 4) The modal particle size (D mode 2. The carbon black according to claim 1, wherein the particle size distribution is greater than 0 and less than or equal to 0.4 μm, and the centrifugal sedimentation method uses anhydrous ethanol as a solvent.

[0055] (Appendix 5) 5. The carbon black according to claim 4, having a mode particle size greater than 0 and less than or equal to 0.3 μm.

[0056] (Appendix 6) 2. The carbon black according to claim 1, having a primary particle size of 10 to 80 nm.

[0057] (Appendix 7) 2. Carbon black according to claim 1, wherein the particle size of the aggregate is 100 to 600 nm.

[0058] (Appendix 8) 2. The carbon black according to claim 1, having a volatile content of 2% by weight to 10% by weight.

[0059] (Appendix 9) 2. The carbon black according to claim 1, having a tinting strength of 90% to 128%.

[0060] (Appendix 10) 2. Use of carbon black as defined in appendix 1 for use in coatings.

[0061] (Appendix 11) 11. The use according to claim 10, wherein the coating is an ink, a metallic paint or a color paste.

Claims

1. A carbon black having a full width at half maximum (FWHM) greater than 0 and less than 0.3 μm as measured by a centrifugal sedimentation method, the centrifugal sedimentation method using anhydrous ethanol as a solvent.

2. 2. The carbon black according to claim 1, wherein the full width at half maximum is greater than 0 and not greater than 0.2 μm.

3. 3. The carbon black according to claim 2, having a full width at half maximum of more than 0 and not more than 0.17 μm.

4. Mode particle size (D) measured by centrifugal sedimentation method ｍｏｄｅ 2. The carbon black according to claim 1, wherein the particle size distribution is greater than 0 and less than or equal to 0.4 μm, and the centrifugal sedimentation method uses absolute ethanol as a solvent.

5. 5. The carbon black according to claim 4, having a mode particle size of greater than 0 and not greater than 0.3 μm.

6. 2. The carbon black according to claim 1, having a primary particle size of 10 to 80 nm.

7. 2. The carbon black according to claim 1, wherein the particle size of the aggregates is 100 to 600 nm.

8. 2. The carbon black according to claim 1, having a volatile content of from 2% by weight to 10% by weight.

9. 2. The carbon black according to claim 1, having a tinting strength of from 90% to 128%.

10. 2. Use of the carbon black according to claim 1 in a coating.

11. The use according to claim 10, wherein the coating is an ink, a metallic paint or a colour paste.

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