GLASS FRIT, COATED ARTICLE INCLUDING A BLACK ENAMEL COATING FORMED FROM THE SAME, AND METHOD FOR MANUFACTURING THE COATED ARTICLE

Abstract

A glass frit for forming a black enamel coating includes Si at 6.5 mol % to 6.9 mol %, B at 9.0 mol % to 9.3 mol %, Bi at 13.0 mol % to 13.4 mol %, Zn at 6.0 mol % to 6.3 mol %, and Al at 1.5 mol % to 2.0 mol %, and Co, Ni, and Fe, wherein a total amount of Co, Ni, and Fe is 2.9 mol % to 3.5 mol % of the glass frit in a molar ratio.

Claims

1. A glass frit for forming a black enamel coating comprising Si at 6.5 mol % to 6.9 mol %, B at 9.0 mol % to 9.3 mol %, Bi at 13.0 mol % to 13.4 mol %, Zn at 6.0 mol % to 6.3 mol %, and Al at 1.5 mol % to 2.0 mol %, and Co, Ni, and Fe, wherein a total amount of Co, Ni, and Fe is 2.9 mol % to 3.5 mol % of the glass frit in a molar ratio.

2. The glass frit of claim 1, wherein a content of Co is 1 to 2 mol %, a content of Ni is 0.5 to 1.1 mol %, and a content of Fe is 0.5 to 1.5 mol % of the glass frit in a molar ratio.

3. The glass frit of claim 2, comprising Si at 6.6 mol % to 6.8 mol %, B at 9.0 mol % to 9.2 mol %, Bi at 13.1 mol % to 13.3 mol %, Zn at 6.1 mol % to 6.3 mol %, Al at 1.7 mol % to 1.8 mol %, Co at 1.0 mol % to 2.0 mol %, Ni at 0.5 mol % to 1.1 mol %, and Fe at 0.5 mol % to 1.5 mol % in a molar ratio.

4. The glass frit of claim 1, further comprising at least one selected from Na and Li at more than 0 and less than 1 mol %.

5. A composition for forming a black enamel coating, comprising: the glass frit of claim 1; and an organic vehicle.

6. The composition of claim 5, wherein the composition does not include a pigment for developing a black color.

7. A coated article comprising: a transparent substrate, a multilayer thin film coating disposed on the transparent substrate, and a patterned portion having a black enamel coating formed on at least part of the transparent substrate as a predetermined pattern, wherein the multilayer thin film coating includes a first dielectric layer, a metallic functional layer having an infrared reflection function, and a second dielectric layer, which are sequentially disposed in a direction away from the transparent substrate, and the black enamel coating is formed from a glass frit comprising Si at 6.5 mol % to 6.9 mol %, B at 9.0 mol % to 9.3 mol %, Bi at 13.0 mol % to 13.4 mol %, Zn at 6.0 mol % to 6.3 mol %, Al at 1.5 mol % to 2.0 mol %, and Co, Ni, and Fe, wherein a total amount of Co, Ni, and Fe is 2.9 mol % to 3.5 mol % of the glass frit in a molar ratio.

8. The coated article of claim 7, wherein a surface roughness (Ra) of the black enamel coating is less than 1 μm.

9. The coated article of claim 7, wherein CIELAB color coordinates (a* and b*) of a reflection color of a surface, on which side the black enamel coating is not formed in a patterned portion, are −1.0 to 1.0.

10. The coated article of claim 7, wherein a thickness of the black enamel coating is from 5 μm to 30 μm.

11. A method for manufacturing a coated article, comprising: printing a composition for forming a black enamel coating so as to have a predetermined pattern on at least part of a transparent substrate having a multilayer thin film coating thereon; and forming a patterned portion including the black enamel coating by carrying out a heat treatment of the transparent substrate on which the multilayer thin film coating and the composition for forming the black enamel coating are formed, wherein the composition for forming the black enamel coating comprises a glass frit comprising Si at 6.5 mol % to 6.9 mol %, B at 9.0 mol % to 9.3 mol %, Bi at 13.0 mol % to 13.4 mol %, Zn at 6.0 mol % to 6.3 mol %, Al at 1.5 mol % to 2.0 mol %, and Co, Ni, and Fe, wherein a total amount of Co, Ni, and Fe is 2.9 mol % to 3.5 mol % of the glass frit in a molar ratio, and an organic vehicle, and the multilayer thin film coating comprises a first dielectric layer, a metallic functional layer having an infrared reflection function, and a second dielectric layer, which are sequentially disposed in a direction away from the transparent substrate.

12. The manufacturing method as claimed in claim 11, wherein the heat treatment is carried out at a temperature of 630° C. to 730° C. for 150 seconds to 300 seconds.

13. The manufacturing method as claimed in claim 11, wherein components in the glass frit are entirely melted by the heat treatment so as to exist as one phase.

14. The manufacturing method as claimed in claim 11, further comprising drying and preheating the composition for forming the black enamel coating before the heat treatment.

15. The manufacturing method as claimed in claim 11, wherein the heat treatment is a tempering process of the transparent substrate.

Description

EXPERIMENTAL EXAMPLE

[0069] A glass frit including metal oxides with mole ratios (mol %) as expressed in Table 1 is prepared.

TABLE-US-00001 TABLE 1 SiO.sub.2 B.sub.2O.sub.3 Bi.sub.2O.sub.3 ZnO Al.sub.2O.sub.3 Co.sub.3O.sub.4 NiO Fe.sub.2O.sub.3 Exemplary 25.3 17.0 24.8 23.1 3.3 2.4 3.0 1.2 Embodiment 1 Exemplary 25.3 17.0 24.8 23.1 3.3 1.2 3.0 2.4 Embodiment 2 Exemplary 25.3 17.0 24.8 23.0 3.3 1.5 3.7 1.5 Embodiment 3 Exemplary 25.3 1.72 24.8 23.2 3.3 2.2 2.0 2.0 embodiment 4 Comparative 25.2 16.9 24.7 23.7 3.3 6.2 0 0 Example 1 Comparative 25.2 16.9 24.7 23.8 3.3 0 0 6.0 Example 2 Comparative 25.4 17.0 24.8 22.2 3.3 0 7.3 0 Example 3 Comparative 25.4 17.2 24.9 20.1 3.3 2.2 3.4 3.4 Example 4 Comparative 25.4 17.2 24.8 21.7 3.3 2.2 2.7 2.7 Example 5 Comparative 30.4 20.4 24.8 11.6 3.5 1.2 4.0 4.0 Example 6 Comparative 24.7 16.5 24.2 3.2 6.7 11.3 6.7 6.7 Example 7

[0070] In the exemplary embodiments and comparative examples, values that are changed by the mole ratios (mol %) of atoms of the respective glass frits are expressed in Table 2.

TABLE-US-00002 TABLE 2 Co + Ni + Si B Bi Zn Al Co Ni Fe Fe O Exemplary 6.7 9.0 13.2 6.1 1.8 1.9 0.8 0.6 3.3 59.8 Embodiment 1 Exemplary 6.8 9.1 13.3 6.2 1.8 1.0 0.8 1.3 3.1 59.9 Embodiment 2 Exemplary 6.8 9.1 13.3 6.2 1.8 1.2 1.0 0.8 3.0 59.8 Embodiment 3 Exemplary 6.7 9.1 13.1 6.1 1.7 1.7 0.5 1.1 3.3 59.9 Embodiment 4 Comparative 6.4 8.6 12.6 6.1 1.7 4.8 0 0 4.8 59.8 Example 1 Comparative 6.7 8.9 13.1 6.3 1.7 0 0 3.2 3.2 60.1 Example 2 Comparative 7 9.4 13.8 6.2 1.8 0 2 0 2 59.8 Example 3 Comparative 6.6 9.0 13.0 5.3 1.7 1.7 0.9 1.8 4.4 60.0 Example 4 Comparative 6.7 9.0 13.0 5.7 1.7 1.7 0.7 1.4 3.8 59.9 Example 5 Comparative 7.7 10.3 12.6 2.9 1.8 0.9 1.0 2.0 3.9 60.7 Example 6 Comparative 5.6 7.4 10.9 0.7 3.0 7.6 1.5 3.0 12.1 60.2 Example 7

[0071] By using the obtained glass frit, the composition (or the paste) for forming a black enamel coating configured with 76% of the glass frit, 8.4% of 2-(2-butoxyethoxy)ethyl acetate, 12.5% of terpineol, and 3.1% of ethyl cellulose, and it is then printed on a Planitherm Dura Plus (a brand name, a glass substrate to which a single Low-E coating is applied) that is a Low-E glass manufactured by Glass Industry Co., Ltd. Korea according to a screen printing method. After this, it is dried for more than twenty minutes at a temperature of 100° C., and it is heat-treated for 230 seconds at 700° C. thereby obtaining a coated article to which the black enamel coating is formed.

[0072] Each the coated article is evaluated as follows.

[0073] Evaluation of Black Color Quality

[0074] The color coordinates is measured by reflecting the color on the opposite side on which no black enamel coating is formed. When the absolute values of a* and b* of the color coordinates are less than 1, they may be seen to express an excellent black color.

[0075] Measurement of Surface Roughness

[0076] The roughness is measured on the side on which the black enamel coating is formed.

[0077] When the surface roughness is less than 1, it may be seen to have a commercially excellent surface.

[0078] Evaluation of Acid Resistance

[0079] The state of the black enamel coating is evaluated as follows after being exposed to a 3% HCl aqueous solution at room temperature for five minutes.

[0080] 1: No changes

[0081] 2: Slight deterioration of gloss is generated.

[0082] 3: Change of color on the surface is imperceptible and the gloss is somewhat deteriorated.

[0083] 4: Substantial changes of color on the surface are observed, and the coating is easily peeled off by physical scratches.

[0084] 5: Enamel coating is peeled from the substrate.

[0085] The cases of 1 to 3 may have commercially usable acid resistance.

[0086] The results are expressed in Table 3.

TABLE-US-00003 TABLE 3 Evaluation of black color (Reflection color on non-coated Surface side) roughness Acid a* B* (μm) resistance Exemplary −0.35 −0.62 0.69 3 Embodiment 1 Exemplary −0.39 0.15 0.83 3 Embodiment 2 Exemplary −0.28 0.32 0.86 3 Embodiment 3 Exemplary 0.43 −0.77 0.69 2 Embodiment 4 Comparative 0.82 −5.09 0.13 3 Example 1 Comparative 5.43 4.79 0.33 3 Example 2 Comparative 0.48 9.87 0.71 3 Example 3 Comparative 1.52 −0.69 7.48 3 Example 4 Comparative 1.12 −0.18 3.67 3 Example 5 Comparative −0.03 −2.46 4.54 3 Example 6 Comparative 0.2 −1.47 11.89 4 Example 7

[0087] As expressed in Table 3, according to exemplary embodiments of the present invention, the absolute values of a* and b* values of the color coordinates are less than 1, so it is found that the excellent black color is realized without including a black pigment. Further, when applied to the glass substrate on which a multilayer thin film coating including a metallic functional layer with an infrared ray reflection function is formed, the surface roughness is less than 1 μm, showing an excellent surface characteristic. In addition, it is found that, regarding the evaluation of acid resistance, the gloss deteriorated degree indicates acid resistance of equal to or greater than grade 3.0n the contrary, compared with the glass frit in the comparative examples, when only one of elements of Co, Ni, and Fe is included as shown in Comparative Examples 1-3, it is found that, even when the content of the above included element is in a range of their sum in the present invention, quality of the black color is deteriorated. Further, when Co, Ni, and Fe are all included but their sum or a content of one element is not included in the range of the present invention as shown in Comparative Examples 4-7, it is found that it is bad at the surface roughness or the acid resistance, or it fails to express the excellent black color.

[0088] The present invention is not limited to the exemplary embodiments and may be produced in various forms, and it will be understood by those skilled in the art to which the present invention pertains that exemplary embodiments of the present invention may be implemented in other specific forms without modifying the technical spirit or essential features of the present invention. Therefore, it should be understood that the aforementioned exemplary embodiments are illustrative in terms of all aspects and are not limited.