Middle coating with ceramic crack simulating effect and preparation method thereof

Abstract

The invention provides floating coat paint with a ceramic crack simulating effect and a preparation method thereof, and relates to the field of paint. The invention discloses a polyvinyl alcohol water-based paint, which is prepared from the following raw materials in parts by weight: 20 to 30 parts of polyvinyl alcohol, 63.7 to 76.5 parts of water, 1.3 to 1.8 parts of auxiliaries and 2 to 5 parts of filler. The preparation method comprises the following steps: dispersing the polyvinyl alcohol, the water and the defoaming agent at 1500 to 2000 rpm for 15 to 30 minutes; then adding the filler and the thickening agent, and dispersing for 15 to 30 minutes at the speed of 1500 to 2000 rpm (revolutions per minute); and adding the rest of the auxiliary agent, and dispersing for 5-10 minutes at 500-800 rpm, thereby obtaining the product. Compared with the traditional crack lacquer which generates the crack effect by virtue of different shrinkage rates of a finish coat and a primer coat, the floating coat provided by the invention has the advantages that cracks are generated by virtue of non-uniform shrinkage rate of a single finish coat layer, the floating coat can be suitable for different finish coats and primer coats, the application range is wide, and the presented crack effect is also increased.

Description

Technical Field

[0001] The invention relates to the field of coatings, and in particular to a mid-coat with a porcelain-like crack effect and a preparation method thereof. Background Art

[0002] Crackle paint is a unique indoor wall decoration material, which has gradually emerged in the building decoration industry in recent years and has been favored by more and more users. With its distinctive artistic charm and unique decorative effect, it has become an indispensable part of high-end home decoration.

[0003] Existing crackle paints for indoor walls usually consist of two parts, a base layer and a surface layer. The base layer is a resin with good softness, while the surface layer contains more pigment fillers and less resin, which makes the surface layer easy to shrink during the drying process. When the shrinkage rate of the surface layer is greater than that of the base layer, stress will be generated inside the coating. When the stress exceeds the tensile strength of the coating material, cracks will appear in the coating. That is, by matching the soft base layer and the hard surface layer, the shrinkage degree of the base layer and the surface layer can be different, resulting in stress cracking and forming a crack effect.

[0004] However, the materials used in existing crackle paints are oily, which has a great impact on the environment and is not suitable for home interior decoration. In addition, the selection of primers and topcoats is narrow. The primers and topcoats of crackle paints on the market are basically sold in sets, so the crack effects and hand feel performance formed are limited by the products on the market, and the range of crack effects that can be selected is small. Summary of the invention

[0005] The purpose of the present invention is to provide a mid-coat with a porcelain-like crack effect, which can make the topcoat lose water quickly and unevenly. The topcoat itself has different shrinkage rates inside and outside to produce a crack effect, and is applicable to most topcoats on the market.

[0006] The present invention solves the technical problem by adopting the following technical solutions.

[0007] On the one hand, an embodiment of the present invention provides a mid-coat with a porcelain-like crack effect, which includes the following raw materials by weight: 20-30 parts of polyvinyl alcohol, 63.7-76.5 parts of water, 1.3-1.8 parts of additives, and 2-5 parts of fillers.

[0008] In some embodiments of the present invention, the average degree of polymerization of the polyvinyl alcohol is 1000-2000. It should be noted that in the present invention, the average degree of polymerization of the polyvinyl alcohol used is 1000-2000. Within this range, the mid-coat is easily atomized, which is convenient for construction, and no sagging will occur after construction on the wall surface. However, when the degree of polymerization is lower than 1000, sagging is likely to occur. When the degree of polymerization is higher than 2000, more water needs to be added to reduce the viscosity of the mid-coat to achieve atomization, which is not convenient for construction.

[0009] In some embodiments of the present invention, the degree of polymerization of the polyvinyl alcohol is 1500. Under this degree of polymerization, the atomization performance and heat storage of the mid-coat coating are both optimal.

[0010] In some embodiments of the present invention, the above-mentioned auxiliary agent includes the following raw materials by weight: 0.1-0.4 parts of defoamer, 0.2-0.4 parts of preservative and mildew-proof agent, 0.5-1.5 parts of thickener. In the present invention, the total amount of defoamer, preservative and mildew-proof agent and thickener is the total amount of auxiliary agent.

[0011] Among them, defoamers effectively inhibit the formation of bubbles in the coating, reduce or eliminate bubbles and foam in the coating, and thus ensure the flatness and smoothness of the coating surface. Furthermore, the addition of defoamers can avoid the problem of uneven coating construction caused by bubbles, reduce the number of construction times, and improve efficiency. Defoamers can also stabilize bubbles in the coating to prevent them from regenerating, thereby improving the stability and durability of the product.

[0012] Anticorrosive and mildew-proof agents have the dual effects of mildew and corrosion prevention. On the one hand, they can effectively inhibit microorganisms in the paint, such as bacteria, fungi, yeast, etc., destroy mildew, and stop the growth of mildew. By inhibiting the metabolism and transaminase system of mildew, they destroy the function and energy release system of mildew cells, thereby achieving mildew-proof effects. On the other hand, they can prevent the paint from getting moldy and deteriorating, thereby extending the storage time and use time of the paint. At the same time, it will not cause any impact on the paint itself, is easily soluble in water, and has good compatibility with various surfactants and other chemical raw materials, and has no negative impact on the various properties of the paint.

[0013] Thickeners can increase the viscosity, making the paint easier to apply, reducing sagging and dripping, and improving construction efficiency. They can also increase the force between the paint and the wall, making it less likely to fall off. Thickeners can also change the rheological properties of the paint to adapt to different construction methods and coating processes, ensuring the uniformity and construction quality of the paint.

[0014] In some embodiments of the present invention, the defoamer is a polyether defoamer, such as San Nopco SN-318, BYK 012, and Haichuan 8034A. The preferred defoamer is BYK-012.

[0015] In some embodiments of the present invention, the antiseptic and mildew preventer is one of isothiazolinone, formaldehyde, and benzimidazole, such as POLYPHASE 7026 of ACTICIDE MV Arxada, BIT20 of Dow, and MBS5050 of Hofmann. The preferred antiseptic and mildew preventer is MBS 5050.

[0016] In some embodiments of the present invention, the thickener is an acrylic acid alkali swelling thickener, such as Dow's TT-615 and TT-935, Wanhua's A401 and A801. Preferably, the thickener is ASE-60.

[0017] In some embodiments of the present invention, the filler is diatomaceous earth. In the present invention, diatomaceous earth is used as a filler, and by utilizing its porous structure and controlling the amount of diatomaceous earth added, the midcoat can achieve the expected water absorption effect and improve the adhesion of the topcoat.

[0018] On the other hand, an embodiment of the present invention provides a method for preparing a mid-coat with a porcelain-like crack effect, comprising the following steps:

[0019] S1, disperse polyvinyl alcohol, water and defoamer at 50-60°C and 1500-2000 rpm for 15-30 min;

[0020] S2, add filler and thickener, and disperse at high speed at 1500-2000rpm for 15min-30min;

[0021] S3, add the remaining additives and disperse at 500-800rpm for 5-10min.

[0022] When preparing the mid-coat coating of the present invention, the polyvinyl alcohol is first dispersed under high-speed stirring, so that the polyvinyl alcohol can be fully dispersed and is easy to mix with other raw materials.

[0023] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects:

[0024] The mid-coat provided by the present invention has good water absorption. When in use, the mid-coat is applied to the surface of the primer, and then the topcoat is applied. The mid-coat will quickly absorb water from the topcoat. When the water content in the topcoat decreases rapidly, the topcoat will shrink in volume, and the volume shrinkage of the topcoat is related to the distance of the topcoat material from the mid-coat. The side close to the mid-coat (i.e., the side where the topcoat contacts the mid-coat) has a fast water reduction and a large volume shrinkage; the side far away (i.e., the outermost side of the topcoat) has a general water loss effect and a small volume shrinkage; due to the difference in volume shrinkage rate inside and outside the topcoat, an uneven shrinkage is formed in the topcoat layer, resulting in a stress difference, and finally a crack effect occurs. Compared with traditional crack paint, which relies on the different shrinkage rates of the topcoat and the primer coating to produce a crack effect, the mid-coat provided by the present invention causes a single topcoat layer to shrink unevenly to produce cracks. It can be applied to different topcoats and primers, has a wide range of use, and can present more crack effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 This is a crack effect diagram of Example 1 of the present invention;

[0027] Figure 2 This is a crack effect diagram of Example 2 of the present invention;

[0028] Figure 3 This is a crack effect diagram of Example 3 of the present invention;

[0029] Figure 4 This is a crack effect diagram of Comparative Example 1 of the present invention;

[0030] Figure 5 This is a crack effect diagram of Comparative Example 2 of the present invention;

[0031] Figure 6 This is a crack effect diagram of Comparative Example 3 of the present invention;

[0032] Figure 7 This is a crack effect diagram of Comparative Example 4 of the present invention;

[0033] Figure 8 This is a crack effect diagram of Comparative Example 5 of the present invention; DETAILED DESCRIPTION

[0034] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0035] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to specific embodiments.

[0036] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0037] Example 1

[0038] The intermediate coating of this embodiment was prepared as follows

[0039] S1: Put 25 parts of polyvinyl alcohol, 68.35 parts of water, and 0.3 parts of defoamer (BYK-012) into container A, disperse at high speed at 1500-2000 rpm for 30 min until it is fully opened, and the temperature in the stirrer is 50° C. when stirring, and place it for standby;

[0040] S2: Add 5 parts of diatomaceous earth (499 from Yiruishi (Shanghai) Investment Management Co., Ltd.) and 1 part of thickener (ASE-60 from Dow) into container A, and disperse at high speed at 1500-2000 rpm for 30 min;

[0041] S3: Add 0.35 parts of bactericidal preservative (MBS 5050 from Hofmann) and stir at 500-800 rpm for 10 min; the finished product is obtained.

[0042] In this embodiment, the average degree of polymerization of polyvinyl alcohol is 1500.

[0043] Example 2

[0044] S1: Put 20 parts of polyvinyl alcohol, 76.2 parts of water and 0.1 parts of defoaming agent into container A, disperse at high speed at 1500-2000 rpm for 15min-30min until it is fully opened and the temperature in the stirrer is 50°C when the stirrer is stirring, and place it for standby;

[0045] S2: Add 2 parts of diatomaceous earth and 1.5 parts of thickener into container A, and disperse at high speed at 1500-2000 rpm for 15min-30min;

[0046] S3: Add 0.2 parts of bactericidal preservative and stir at 500-800 rpm for 5-10 min to obtain the finished product.

[0047] The raw materials in this example are the same as those in Example 1.

[0048] Example 3

[0049] S1: Put 30 parts of polyvinyl alcohol, 63.7 parts of water and 0.4 parts of defoaming agent into container A, disperse at high speed at 1500-2000 rpm for 15min-30min until it is fully opened and the temperature in the stirrer is 50°C when the stirrer is stirring, and place it for standby;

[0050] S2: Add 5 parts of diatomaceous earth and 0.5 parts of thickener into container A, and disperse at high speed at 1500-2000 rpm for 15min-30min;

[0051] S3: Add 0.4 parts of bactericidal preservative and stir at 500-800 rpm for 5-10 min to obtain the finished product.

[0052] The raw materials in this example are the same as those in Example 1.

[0053] Comparative Example 1

[0054] The difference from Example 1 is that in this comparative example, the degree of polymerization of the polyvinyl alcohol in step S1 is 500. The remaining raw materials and steps are the same as those in Example 1.

[0055] Comparative Example 2

[0056] The difference from Example 1 is that in this comparative example, the degree of polymerization of the polyvinyl alcohol in step S1 is 2500. The remaining raw materials and steps are the same as those in Example 1.

[0057] Comparative Example 3

[0058] The difference from Example 1 is that in this comparative example, the diatomaceous earth in step S2 is replaced by heavy calcium. The remaining raw materials and steps are the same as those in Example 1.

[0059] Comparative Example 4

[0060] The difference from Example 1 is that in this comparative example, bentonite is used as the thickener in step S2. The remaining raw materials and steps are the same as those in Example 1.

[0061] Comparative Example 5

[0062] The difference from Example 1 is that in this comparative example, no thickener is added in step S2. The remaining raw materials and steps are the same as those in Example 1.

[0063] Experimental example

[0064] 1. The mid-coat coatings of Examples 1-2 and Comparative Examples 1-5 were used as the objects to investigate the atomization, sagging and heat storage properties of each mid-coat coating. The results are shown in Table 1.

[0065] Table 1 Performance of midcoat coatings of Examples 1-2 and Comparative Examples 1-5

[0066]

[0067]

[0068] Among them, atomization: is to use a wet film thickness gauge to measure the wet film thickness at different points on the test plate after spraying, refer to the international standard ISO2808 "Paints and varnishes-Determination of film thickness". The greater the thickness difference, the worse the atomization effect, so as to evaluate the atomization uniformity of the spray.

[0069] The sag property is evaluated by spraying the same mass of paint on the same area of ​​the board, then tilting it 60° and observing the flow of the paint on the inclined board.

[0070] The thermal storage state refers to the state in the container in the standard GB / T9756 "Synthetic resin emulsion interior wall paint". The paint is stored in a 50°C oven for 7 days, then placed under standard conditions. After the temperature returns to 25°C, the state of the paint is observed to evaluate the thermal storage performance of the product.

[0071] It can be seen from Table 1 that: comparing Example 1 and Comparative Examples 1-2, the coating of polyvinyl alcohol with a degree of polymerization of 500 selected in Comparative Example 1 is easy to atomize, but is prone to sagging; while polyvinyl alcohol with a degree of polymerization of 2500 selected in Comparative Example 2 has a high viscosity and poor atomization during the spraying process, resulting in uneven distribution of the coating, which in turn leads to uneven water absorption and uneven cracks, with some parts having cracks and some parts not having cracks.

[0072] It can be seen from Comparative Example 3 that diatomaceous earth can enhance the water absorption rate of the paint film, make the crack effect better, and improve the adhesion with the next coating.

[0073] It can be seen from Comparative Examples 4-5 that without adding a thickener, the paint film is prone to sagging after spraying, while adding bentonite will form a jelly state, which will become a granular state after stirring.

[0074] The embodiments 1-3 provided by the present invention have good atomization performance, and when sprayed on the primer surface, there is no sagging phenomenon, and the heat storage performance is excellent.

[0075] 2. Take the intermediate coatings of Examples 1-3 and Comparative Examples 1-5 as the object, first roll the primer A (Carpoly Art Paint Multifunctional Fresh Primer KRD0014, diluted with 10%) on the simulated wall substrate, and then spray the intermediate coating (diluted with 10%), and then spray the high PVC topcoat (Carpoly Odor-free Wall Paint JAC3000, diluted with 30%). After standing for 12 hours, observe the crack effect. The crack effect diagram is as shown in the attached figure. Figure 1-8 shown.

[0076] From the attached Figure 1-3 It can be seen that the cracked wall surface obtained by the intermediate coating of Examples 1-3 has uniform and regular cracks, and visually has a porcelain-like crack effect. However, the cracks of Comparative Examples 1-5 are uneven, of varying sizes, and have sagging, and do not have a porcelain-like crack effect.

[0077] In summary, the mid-coat provided by the embodiment of the present invention has good water absorption. When in use, the mid-coat is applied to the surface of the primer, and then the topcoat is applied. The mid-coat will quickly absorb water from the topcoat. When the water content in the topcoat decreases rapidly, the topcoat will shrink in volume, and the volume shrinkage of the topcoat is related to the distance of the topcoat material from the mid-coat. The one closer to the mid-coat (i.e., the side where the topcoat contacts the mid-coat) has a fast water reduction and a large volume shrinkage; the one farther away (i.e., the outermost side of the topcoat) has a general water loss effect and a small volume shrinkage; due to the difference in volume shrinkage rate inside and outside the topcoat, an uneven shrinkage is formed in the topcoat layer, resulting in a stress difference, and finally a crack effect occurs. Compared with traditional crack paint, which relies on the different shrinkage rates of the topcoat and the primer coating to produce a crack effect, the mid-coat provided by the present invention makes the single topcoat layer shrink unevenly to produce cracks, which can be applied to different topcoats and primers, has a wide range of use, and the crack effects that can be presented are also increased.

[0078] The embodiments described above are part of the embodiments of the present invention, rather than all of the embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Claims

1. A mid-coat with a porcelain-like crack effect, characterized in that: The raw materials include the following by weight: 20-30 parts of polyvinyl alcohol, 63.7-76.5 parts of water, 1.3-1.8 parts of auxiliary agent and 2-5 parts of filler.

2. The mid-coat with imitation porcelain crack effect according to claim 1, characterized in that: The degree of polymerization of the polyvinyl alcohol is 1000-2000.

3. The mid-coat with imitation porcelain crack effect according to claim 1, characterized in that: The degree of polymerization of the polyvinyl alcohol is 1500.

4. The mid-coat with imitation porcelain crack effect according to claim 1, characterized in that: The auxiliary agent comprises the following raw materials in parts by weight: 0.1-0.4 parts of defoaming agent, 0.2-0.4 parts of preservative and mildew preventer, and 0.5-1.5 parts of thickener.

5. The mid-coat with imitation porcelain crack effect according to claim 4, characterized in that: The defoamer is a mixture of polyether silicone mineral oil.

6. The mid-coat with imitation porcelain crack effect according to claim 4, characterized in that: The antiseptic and mildew preventer is one of isothiazolinone, formaldehyde and benzimidazole.

7. The mid-coat with imitation porcelain crack effect according to claim 4, characterized in that: The thickener is an acrylic acid alkali swelling thickener.

8. The mid-coat with imitation porcelain crack effect according to claim 1, characterized in that: The filler is diatomaceous earth.

9. A method for preparing a mid-coat with a porcelain-like crack effect as claimed in any one of claims 1 to 8, comprising the following steps: S1, disperse polyvinyl alcohol, water and defoamer at 1500-2000 rpm for 15 min-30 min; S2, add filler and thickener, and disperse at 1500-2000rpm for 15min-30min; S3, add the remaining additives and disperse at 500-800rpm for 5-10min.

Images