A high-stability black inorganic coating and its preparation process

Abstract

The present invention relates to the technical field of inorganic coatings, and discloses a high-stability black inorganic coating and a preparation process thereof. The inorganic coating comprises the following components, calculated by mass percentage: silica sol: 15-20%; styrene-acrylic emulsion: 8-9%; hydroxyethyl cellulose: 0.6-0.8%; nonionic dispersant: 0.3-0.5%; wetting agent: 0.3-0.4%; defoamer: 0.3-0.5%; stabilizer: 0.2-0.4%; inorganic filler: 28-32%; cosolvent: 0.8-1.2%; organic carbon black slurry: 1.5-2%; the balance being deionized water. The present invention appropriately lowers the pH value by replacing the main film-forming substances in the system, thereby reducing the damage to the color paste particles and the system caused by high alkalinity. At the same time, an alkali-resistant dispersant is used to protect the color paste particles, and a stabilizer is used in combination to stabilize the system, thereby reducing problems such as floating color, blooming, and flocculation.

Description

Technical Field

[0001] The present invention relates to the technical field of inorganic coatings, in particular to a high-stability black inorganic coating and a preparation process thereof. Background Art

[0002] Inorganic coatings have excellent weather resistance, air permeability, fire resistance, as well as excellent mildew resistance and environmental protection properties. With the market's preference for inorganic coatings in the past two years, they have been widely used in indoor and outdoor wall decoration.

[0003] Due to the presence of alkali metal ions in inorganic coatings, the pH of inorganic coating systems is often highly alkaline (pH>11). When organic colorants commonly used in architectural coatings are added to inorganic coatings, the strong alkalinity can destroy the wetting agents surrounding the colorant particles, exposing them and causing flocculation. This destabilizes the colorant system and can lead to problems such as floating and blooming. For example, when organic carbon black slurry is added to an inorganic coating, the finished product has a high black chroma, but poor storage stability and susceptibility to flocculation. When inorganic iron black slurry is added to an inorganic coating, the finished product has better stability, but the resulting black chroma is not high.

[0004] Therefore, it is an urgent need of the present invention to provide a high-stability black inorganic coating and a preparation process thereof, which solves the stability problem between the black paste and the inorganic coating while ensuring the black chroma. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the present invention provides a high-stability black inorganic coating and its preparation process. The present invention solves the stability problem between the black paste and the inorganic coating while ensuring the black chroma of the coating.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0007] A high-stability black inorganic coating comprises the following components by mass percentage:

[0008]

[0009]

[0010] Preferably, the silica sol is Orun The styrene-acrylic emulsion is Wanhua Archsol 8653; the hydroxyethyl cellulose is Dow QP-30000H; the nonionic dispersant is Clariant Dispersogen 2774; the wetting agent is Evonik ZetaSperse 179; the defoaming agent is Tego-805; the stabilizer is Clariant Dispersogen SPS; the inorganic filler is mainly calcium carbonate, the cosolvent is Dow Coasol 290 Plus; and the organic carbon black slurry is BASF Dispers Black 0066.

[0011] Preferably, the inorganic coating of the present invention comprises the following components in percentage by mass:

[0012]

[0013] Preferably, the inorganic coating of the present invention comprises the following components in percentage by mass:

[0014]

[0015]

[0016] Preferably, the inorganic coating of the present invention comprises the following components in percentage by mass:

[0017]

[0018] Another object of the present invention is to disclose a preparation process of the above-mentioned high-stability black inorganic coating, comprising the following steps:

[0019] (1) Add a nonionic dispersant and a portion of deionized water to an organic carbon black slurry, and stir thoroughly in a 60°C water bath to prepare a mixture A;

[0020] (2) Adding the styrene acrylic emulsion and the silica sol to the stabilizer under stirring to prepare a mixture B;

[0021] (3) Adding hydroxyethyl cellulose, a wetting agent, a portion of a defoaming agent, and an inorganic filler to another portion of deionized water and grinding at high speed to a fineness of less than 50 μm, and then adding the remaining amount of the defoaming agent and the cosolvent to prepare a mixture C;

[0022] (4) While stirring, add mixture A to mixture C. After the mixture is fully dispersed, add mixture B and the remaining deionized water.

[0023] The amount of deionized water added in steps (1) and (3) only needs to be sufficient to dissolve the ingredients. In step (3), 1 / 2-2 / 3 of the defoaming agent is added first, followed by the remainder.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] This invention replaces the primary film-forming substance in the system (using silica sol instead of silicate) to appropriately lower the pH value and reduce the damage to the color paste particles and the system caused by high alkalinity. Furthermore, an alkali-resistant dispersant is used to protect the color paste particles, and a stabilizer is used in conjunction with the system to stabilize the system, thereby reducing problems such as floating color, blurring, and flocculation.

[0026] The present invention achieves the preparation of a highly stable black inorganic coating by improving the preparation process. Stirring under heating conditions increases the movement speed of the color paste particles, allowing them to be more fully dispersed in the system. A dispersant is first added to the color paste to ensure that each particle surface is fully adsorbed with the same charge, preventing flocculation. A stabilizer is first brought into contact with the emulsion and silica sol to ensure that the stabilizer fully combines with the silica sol, thus stabilizing the system and preventing aggregation. DETAILED DESCRIPTION

[0027] The present invention is further described below with reference to the following examples. However, it should be noted that the examples do not limit the scope of protection claimed in the present invention.

[0028] A high-stability black inorganic coating comprises the following components by mass percentage:

[0029]

[0030] Among them, silica sol is Orun The styrene-acrylic emulsion is Wanhua Archsol 8653; the hydroxyethyl cellulose is Dow QP-30000H; the nonionic dispersant is Clariant Dispersogen 2774; the wetting agent is Evonik ZetaSperse 179; the defoaming agent is Tego-805; the stabilizer is Clariant Dispersogen SPS; the inorganic filler is calcium carbonate; the cosolvent is Dow Coasol 290 Plus; and the organic carbon black slurry is BASF Dispers Black 0066.

[0031] In order to illustrate the performance advantages of the black inorganic coating of the present invention, the following is illustrated by comparing Examples 1-3 and Comparative Examples 1-3 in Table 1:

[0032] Table 1 Formulations of Examples 1-3 and Comparative Examples 1-3 (Unit: wt%)

[0033]

[0034]

[0035] The preparation process of the above-mentioned high-stability black inorganic coating comprises the following steps:

[0036] (1) Add a nonionic dispersant and a portion of deionized water to an organic carbon black slurry, and stir thoroughly in a 60°C water bath to prepare a mixture A;

[0037] (2) Adding the styrene acrylic emulsion and the silica sol to the stabilizer under stirring to prepare a mixture B;

[0038] (3) Adding hydroxyethyl cellulose, a wetting agent, a portion of a defoaming agent, and an inorganic filler to another portion of deionized water and grinding at high speed to a fineness of less than 50 μm, and then adding the remaining amount of the defoaming agent and the cosolvent to prepare a mixture C;

[0039] (4) While stirring, add mixture A to mixture C. After the mixture is fully dispersed, add mixture B and the remaining deionized water.

[0040] The amount of deionized water added in steps (1) and (3) only needs to be sufficient to dissolve the ingredients. In step (3), 1 / 2-2 / 3 of the defoaming agent is added first, followed by the remainder.

[0041] The black inorganic coatings of Examples 1-3 and Comparative Examples 1-3 were prepared according to the above preparation process and tested. The results are shown in the following table:

[0042]

[0043]

[0044] As shown in the table above, the combination of a highly alkali-resistant dispersant and stabilizer in Examples 1-3 stabilizes the system, preventing problems such as floating, blurring, and flocculation. Using either agent alone does not achieve the desired storage stability (as seen in Comparative Examples 1 and 2). Compared to Example 1 and Comparative Example 3, the carbon black slurry maintains a high blackness, achieving a higher black chroma than iron black slurry.

[0045] Experiments on the improvement effect of the preparation process of the present invention:

[0046] 1. Prepare a black inorganic coating according to Example 1 by the following steps:

[0047] (1) Add a nonionic dispersant and a portion of deionized water to an organic carbon black slurry, and stir thoroughly in a 60°C water bath to prepare a mixture A;

[0048] (2) Adding the styrene acrylic emulsion and the silica sol to the stabilizer under stirring to prepare a mixture B;

[0049] (3) Add hydroxyethyl cellulose, a wetting agent, 0.2 wt% of a defoamer, and an inorganic filler to another portion of deionized water (the sum of the deionized water added in steps 1 and 3 is 30 wt%) and grind at high speed to a fineness of <50 μm. Then, add 0.1 wt% of a defoamer and a cosolvent to prepare a mixture C.

[0050] (4) While stirring, add mixture A to mixture C. After the mixture is fully dispersed, add mixture B and the balance 11.05 wt% of deionized water.

[0051] 2. Comparative Example 4: Using the formula of Example 1, the following preparation method was used:

[0052] (1) Add hydroxyethyl cellulose to 30 wt% deionized water, stir evenly, then add a wetting agent, 0.2 wt% defoaming agent, and a dispersant;

[0053] (2) Add inorganic fillers and grind at high speed to a fineness of less than 50 μm;

[0054] (3) adding styrene-acrylic emulsion, silica sol, 0.1 wt% defoamer, cosolvent, and the balance 11.05 wt% deionized water under stirring;

[0055] (4) Add organic carbon black slurry and stabilizer.

[0056] Black inorganic coatings were prepared in Example 1 and Comparative Example 4 and tested. The results are shown in the following table:

[0057]

[0058] The present invention achieves the preparation of a highly stable black inorganic coating by improving the preparation process. The present invention first adds a dispersant to the color paste, ensuring that each particle surface is fully adsorbed with the same charge to prevent flocculation. The stabilizer is first brought into contact with the emulsion and silica sol, ensuring that the stabilizer fully combines with the silica sol, thus stabilizing the system and preventing aggregation.

[0059] The technical solutions provided by the embodiments of the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the embodiments of the present invention. The description of the above embodiments is only applicable to help understand the principles of the embodiments of the present invention. At the same time, for those skilled in the art, according to the embodiments of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A high-stability black inorganic coating, characterized in that: It includes the following components in percentage by mass: The balance is deionized water; The silica sol is Orun S308; the styrene-acrylic emulsion is Wanhua Archsol 8653; the hydroxyethyl cellulose is Dow QP-30000H; the nonionic dispersant is Clariant Dispersogen 2774; the wetting agent is Evonik ZetaSperse 179; the defoamer is Tego-805; the stabilizer is Clariant Dispersogen SPS; the inorganic filler is calcium carbonate, the cosolvent is Dow Coasol 290Plus; the organic carbon black slurry is BASF Dispers Black 0066.

2. A high-stability black inorganic coating according to claim 1, characterized in that: It includes the following components in percentage by mass: The balance was deionized water.

3. A high stability black inorganic coating according to claim 1, characterized in that: It includes the following components in percentage by mass: The balance was deionized water.

4. A high-stability black inorganic coating according to claim 1, characterized in that: It includes the following components in percentage by mass: The balance was deionized water.

5. A process for preparing a high-stability black inorganic coating according to any one of claims 1 to 4, characterized in that: The following steps are involved: (1) Add a nonionic dispersant and a portion of deionized water to an organic carbon black slurry, and stir thoroughly in a 60°C water bath to prepare a mixture A; (2) Adding the styrene acrylic emulsion and the silica sol to the stabilizer under stirring to prepare a mixture B; (3) Adding hydroxyethyl cellulose, a wetting agent, a portion of a defoaming agent, and an inorganic filler to another portion of deionized water and grinding at high speed to a fineness of less than 50 μm, and then adding the remaining amount of the defoaming agent and the cosolvent to prepare a mixture C; (4) While stirring, add mixture A to mixture C. After the mixture is fully dispersed, add mixture B and the remaining deionized water.

Images