A water-based acrylic paint, a preparation method and application thereof

Abstract

The application discloses a kind of water-based acrylic coating and its preparation method and application, belong to water-based paint technical field.The water-based acrylic coating provided by the application includes the following mass fraction of preparation raw materials: 18~32 parts of water-based acrylic resin, 0.5~8 parts of pigment, 40~65 parts of filler, 5~30 parts of water, 0.05~0.8 parts of thickening agent, 0.3~1.5 parts of dispersing agent, 0.3~1.5 parts of defoaming agent, 0.8~1.8 parts of film-forming aid;The color base ratio of the coating is 4.2~5.2.The application starts from the three angles of improving coating hardness, constructing rough surface and reducing coating cohesion, uses water-based acrylic coating with high color base ratio, which can effectively improve coating hardness, reduce the contact area after coating close, reduce surface force and cohesion, thereby prevent the adhesion of water-based acrylic coating when stacking contact, improve the anti-adhesion effect of water-based acrylic coating, and the water-based acrylic coating of the application has wide application in material protection, especially metal material protection.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of water-based paint, and particularly relates to a water-based acrylic paint, a preparation method and application thereof. BACKGROUND

[0002] In the field of light corrosion protection, it is common that the components on which the paint has been applied are stacked after drying for a short time. In particular, in the field of net racks, the packing method is to stack a large number of net racks and bind them together. The components in this form are stacked under the action of gravity or external binding, and the coatings on the surfaces of the components will be tightly adhered together due to the strong external force. The commonly used paint in this field is a water-based single-component acrylic paint. Due to the characteristics of thermal adhesion and cold brittleness, the water-based acrylic resin will generate a greater force on the tightly adhered coatings. Under such conditions, when the components stacked together are separated by using external force, the water-based acrylic paint on one side of the substrate will be peeled off due to the external force, and the phenomenon of exposing the metal luster of the substrate bottom will occur.

[0003] The main reason for this phenomenon is that the paint has a certain adhesion after the two net racks or two components are respectively applied with the paint. When the components are stacked, there are three forces in the whole, one is the adhesion between the coating and the substrate, one is the cohesion of the coating, and one is the force generated by the adhesion of the coatings on the surfaces of the two components.

[0004] However, due to the differences in the coating thickness, film forming effect and treatment degree of the substrate of the water-based paint, there is a certain difference in the adhesion of each position of the same paint on the same components. When the components are stacked, the coatings on the surfaces of the two components adhere to each other, and a great force is generated between the coatings. This force is often greater than the cohesion of the coating, and greater than the adhesion between the coating and the substrate. When the two substrates are separated by using external force, the coating of the substrate with weak adhesion will be peeled off by the external force, and the substrate will expose the metal luster.

[0005] At present, the ideas for solving the problem are basically the same, and the solutions are similar, including improving the hardness of the resin and improving the smoothness of the coating surface. For example, technical routes such as mixing acrylic resin and silicone resin, mixing water-based acrylic resin and water-based epoxy ester resin, mixing water-based acrylic resin and silica sol, mixing high-Tg acrylic resin, water-based epoxy resin emulsion and silica sol, etc. The existing technical routes improve the hardness of the coating from the perspective of the resin, thereby achieving the effect of anti-adhesion, but the anti-adhesion effect is general. SUMMARY

[0006] In order to overcome the problems existing in the prior art, one of the purposes of the present application is to provide a water-based acrylic paint, which has good anti-adhesion effect.

[0007] The second object of the present application is to provide a preparation method of the water-based acrylic paint.

[0008] The third object of the present application is to provide an application of the water-based acrylic paint.

[0009] In order to achieve the above objects, the technical scheme adopted by the present application is as follows:

[0010] The first aspect of the present application provides a water-based acrylic paint, which comprises the following raw materials in mass fraction: 18-32 parts of water-based acrylic resin, 0.5-8 parts of pigment, 40-65 parts of filler, 5-30 parts of water, 0.05-0.8 parts of thickening agent, 0.3-1.5 parts of dispersing agent, 0.3-1.5 parts of defoaming agent, and 0.8-1.8 parts of film-forming aid; the color-binder ratio of the paint is 4.2-5.2.

[0011] The inventive concept of the present application is that the anti-adhesion effect of the water-based acrylic paint is effectively improved by the combination of the three methods of increasing the hardness of the paint, constructing a rough surface, and reducing the cohesion of the paint. Firstly, the paint with high color-binder ratio is used in the present application, which is beneficial to increase the hardness of the paint. The color-binder ratio refers to the ratio of the color filler to the binder, the color filler refers to the pigment and the filler, and the binder refers to the pure resin (the resin generally added contains water or solvent, and has a certain solid content, which should be multiplied by the solid content when calculating). The function of the resin in the paint is to bond each component into a whole, the powder wrapping ability of the resin is strong, the surface tension of the system is low, and the color filler has good wettability, that is, the content of the color filler in the paint with high color-binder ratio is high, and the hardness of the obtained coating is also high, and the anti-adhesion effect is good.

[0012] Secondly, the paint with high color-binder ratio can also construct a rough coating surface. When the final state of the coating is uneven, when the components coated with the coating film are stacked, the contact area of the coating contacting with each other will change from the face-to-face contact of the plane to the line-to-line or point-to-point contact of the uneven surface, which greatly reduces the contact area between the coatings. Since the acting force between the coatings is the resultant force between the action points, the smaller the contact area, the smaller the resultant force, which reduces the acting force between the coatings. When the acting force between the coatings is much smaller than the adhesion between the coating and the substrate, when the components are separated, the coating on one of the components will not be torn off due to the too large acting force between the coatings, so as to expose the substrate with metallic luster. That is, the higher the color-binder ratio, the more color fillers exposed on the surface, the rougher the coating surface, and the more conducive to improving the anti-adhesion performance of the coating.

[0013] Finally, the paint with high pigment to binder ratio is conducive to reducing the cohesion of the paint. The more pigments and fillers in the paint with high pigment to binder ratio, the less resin to wrap the pigments and fillers, thereby being conducive to reducing the cohesion of the paint. When the size of the cohesion is lower than the adhesion, the probability of the cohesive failure of the paint when the two components are separated is greatly improved, and the probability of the overall paint peeling and the substrate exposing the metal gloss is reduced.

[0014] Preferably, the pigment to binder ratio of the paint is 4.22-5.1; further preferably 4.4-5.0.

[0015] Preferably, the Mohs hardness of the fillers in the raw materials for preparing the paint is ≥5; further preferably 6-7.

[0016] Preferably, the fillers in the raw materials for preparing the paint include feldspar powder, silica powder or a combination thereof.

[0017] The present application further improves the hardness of the water-based paint and the anti-sticking effect by selecting the fillers with high hardness from the perspective of pigments and fillers. The hardness of the paint layer of the present application is HB, which is the hardness limit of the single-component non-modified water-based acrylic paint.

[0018] Preferably, the minimum film formation temperature of the water-based acrylic resin in the raw materials for preparing the paint is 18-28℃; further preferably 20-25℃.

[0019] Preferably, the solid content of the water-based acrylic resin in the raw materials for preparing the paint is 44-50wt%; further preferably 46-48wt%.

[0020] The water-based acrylic resin of the present application has good powder wrapping capacity and can be used to prepare paint with high pigment to binder ratio. The resin with strong powder wrapping capacity is stable when used to prepare the water-based paint with high pigment to binder ratio. The resin with weak powder wrapping capacity will be directly changed into mud when mixed with the slurry, and cannot be used to successfully prepare the stable water-based paint.

[0021] In the specific embodiments of the present application, the water-based acrylic resin includes at least one of Ross 911, Henghe 2052 or Badifu 998A.

[0022] Preferably, the thickening agent in the raw materials for preparing the paint is selected from low-shear thickening agents; further preferably, the thickening agent includes low-shear polyurethane thickening agent, low-shear alkali-swellable thickening agent or a combination thereof.

[0023] The low shear thickening agent can make the coating have relatively large thixotropy, which can make the coating not level well during drying, and the poor leveling of the coating can cause uneven thickness of the coating, and the thick part of the coating is the main contact position, and the uneven thickness of the coating can cause the contact area of the coating to be small, and then the force is reduced. By using the low shear thickening agent, the surface roughness of the coating can be further improved, and the anti-blocking performance can be improved.

[0024] In the specific embodiment of the present application, the thickening agent comprises at least one of Wanhua U905, Puwei H120 or Ro Menhas 12W.

[0025] In the present application, conventional pigments, dispersants, defoamers or film-forming aids can be used in the present application.

[0026] In the specific embodiment of the present application, the dispersant comprises at least one of Dow 731a, Huirong 2361, Akoma BR85 or BASF 4320.

[0027] In the specific embodiment of the present application, the defoamer is selected from polyether modified silicone defoamer; in the more specific embodiment of the present application, the defoamer comprises at least one of Di Guo 901W, Shen Zhu 6791, Bick BYK-011 or Bick BYK-024.

[0028] In the specific embodiment of the present application, the film-forming aid comprises at least one of alcohol ester twelve, propylene glycol phenyl ether (ppH) and dipropylene glycol butyl ether (DPnB).

[0029] Preferably, in the preparation raw materials of the coating, the mass fraction of the water-based acrylic resin is 20-30 parts; further preferably, 23-28 parts.

[0030] Preferably, in the preparation raw materials of the coating, the mass fraction of the pigment is 0.8-6 parts; further preferably, 1-5 parts.

[0031] Preferably, in the preparation raw materials of the coating, the mass fraction of the filler is 45-60 parts; further preferably, 50-55 parts.

[0032] Preferably, in the preparation raw materials of the coating, the mass fraction of the water is 8-25 parts; further preferably, 10-20 parts.

[0033] Preferably, in the preparation raw materials of the coating, the mass fraction of the thickening agent is 0.08-0.6 parts; further preferably, 0.1-0.5 parts.

[0034] Preferably, in the preparation raw materials of the coating, the mass fraction of the dispersant is 0.4-1.2 parts; further preferably, 0.5-1 part.

[0035] Preferably, the mass fraction of the defoaming agent in the preparation raw materials of the coating is 0.4-1.2 parts; further preferably 0.5-1 part.

[0036] Preferably, the mass fraction of the film-forming aid in the preparation raw materials of the coating is 1-1.5 parts; further preferably 1.1-1.4 parts.

[0037] Preferably, the water-based acrylic coating comprises the following mass fractions of preparation raw materials: 20-30 parts of water-based acrylic resin, 0.8-6 parts of pigment, 45-60 parts of filler, 8-25 parts of water, 0.08-0.6 parts of thickening agent, 0.4-1.2 parts of dispersant, 0.4-1.2 parts of defoaming agent, and 1-1.5 parts of film-forming aid.

[0038] Further preferably, the water-based acrylic coating comprises the following mass fractions of preparation raw materials: 23-28 parts of water-based acrylic resin, 1-5 parts of pigment, 50-55 parts of filler, 10-20 parts of water, 0.1-0.5 parts of thickening agent, 0.5-1 parts of dispersant, 0.5-1 parts of defoaming agent, and 1.1-1.4 parts of film-forming aid.

[0039] Preferably, the preparation raw materials of the water-based acrylic coating further comprise a pH adjuster, an anti-flash rust agent, or a combination thereof; further preferably, the preparation raw materials of the water-based acrylic coating further comprise a pH adjuster and an anti-flash rust agent.

[0040] In the present application, both conventional pH adjusters and anti-flash rust agents can be used in the present application.

[0041] In the specific embodiments of the present application, the pH adjuster comprises at least one of N,N-dimethyl ethanolamine (DMEA), 2-amino-2-methyl-1-propanol (AMP-95), or sodium hydroxide.

[0042] In the specific embodiments of the present application, the anti-flash rust agent is selected from sodium nitrite.

[0043] Preferably, the preparation raw materials of the coating do not contain a leveling agent. Without adding any leveling agent in the present application, the synergistic effect between the above-mentioned preparation raw materials enables the coating to have good anti-adhesion effect even with a hardness of only HB.

[0044] Preferably, the mass fraction of the pH adjuster in the aid is 0.3-1.5 parts; further preferably 0.4-1.2 parts; and more preferably 0.5-1 part.

[0045] Preferably, the mass fraction of the anti-flash rust agent in the aid is 0.03-0.2 parts; further preferably 0.05-0.15 parts; and further preferably 0.08-0.12 parts.

[0046] Preferably, the waterborne acrylic coating comprises the following raw materials in parts by weight: 18-32 parts waterborne acrylic resin, 0.5-8 parts pigment, 40-65 parts filler, 5-30 parts water, 0.05-0.8 parts thickener, 0.3-1.5 parts dispersant, 0.3-1.5 parts defoamer, 0.8-1.8 parts film-forming aid, 0.3-1.5 parts pH adjuster, and 0.03-0.2 parts anti-flash rust agent.

[0047] More preferably, the waterborne acrylic coating comprises the following raw materials in parts by weight: 20-30 parts waterborne acrylic resin, 0.8-6 parts pigment, 45-60 parts filler, 8-25 parts water, 0.08-0.6 parts thickener, 0.4-1.2 parts dispersant, 0.4-1.2 parts defoamer, 1-1.5 parts film-forming aid, 0.4-1.2 parts pH adjuster, and 0.05-0.15 parts anti-flash rust agent.

[0048] More preferably, the waterborne acrylic coating comprises the following raw materials in parts by weight: 23-28 parts waterborne acrylic resin, 1-5 parts pigment, 50-55 parts filler, 10-20 parts water, 0.1-0.5 parts thickener, 0.5-1 part dispersant, 0.5-1 part defoamer, 1.1-1.4 parts film-forming aid, 0.5-1 part pH adjuster, and 0.08-0.12 parts anti-flash rust agent.

[0049] A second aspect of the present invention provides a method for preparing the waterborne acrylic coating described in the first aspect of the present invention, characterized by comprising the following steps:

[0050] The raw materials are mixed to obtain the water-based acrylic coating.

[0051] Preferably, in the preparation method, the mixing order of the raw materials is water, dispersant, waterborne acrylic resin, defoamer, pigment, filler, film-forming aid, and thickener; more preferably, when the aid includes pH adjuster and anti-flash rust agent, the mixing order of the raw materials is water, pH adjuster, dispersant, anti-flash rust agent, waterborne acrylic resin, defoamer, pigment, filler, film-forming aid, and thickener.

[0052] A third aspect of the present invention provides an application of the waterborne acrylic coating described in the first aspect of the present invention in material protection.

[0053] Preferably, the material is selected from metallic materials.

[0054] The beneficial effects of the present application are: the present application starts from the three aspects of improving the hardness of the coating, constructing a rough surface and reducing the cohesion of the coating, adopts the water-based acrylic coating with high pigment-binder ratio, can effectively improve the hardness of the coating, reduce the contact area after the coating is closely attached, reduce the surface force and cohesion, thereby preventing the adhesion of the water-based acrylic coating when the coating is stacked and contacted, and improving the anti-adhesion effect of the water-based acrylic coating. The water-based acrylic coating of the present application has wide application in material protection, especially metal material protection.

[0055] Specifically, compared with the prior art, the present application has the following advantages:

[0056] 1. The hardness of the coating of the present application is improved, not from the perspective of resin, but from the perspective of pigment-binder ratio and filler. The hardness of the filler is much higher than that of the resin. Therefore, the pigment-binder ratio of the present application is increased to 4.2-5.2, and the filler with Mohs hardness of 5 or more is selected. The two aspects work together to improve the hardness of the water-based coating and improve the anti-adhesion effect. The hardness of the coating of the present application is HB, which belongs to the hardness limit of single-component unmodified water-based acrylic coating.

[0057] 2. The present application constructs a rough surface by the coating, so that the final state of the coating is uneven, which greatly reduces the contact area when the coatings are contacted, reduces the force between the coatings, and avoids the adhesion and tearing between the coatings. Specifically, the present application constructs a rough surface of the coating through two aspects: one is to increase the pigment-binder ratio, and the more powder, the rougher the surface of the coating; the other is to use a low shear thickening agent. The low shear thickening agent can make the liquid coating have thixotropy, and the thixotropy can make the wet film not flow flat, and the wet film that does not flow flat is uneven.

[0058] 3. The present application does not add any leveling agent, and through the synergistic effect of the above-mentioned method, the coating can have good anti-adhesion effect even if the hardness is only HB. DETAILED DESCRIPTION

[0059] The content of the present application is further illustrated by specific examples. It should also be understood that the following examples are only used to further illustrate the present application, and cannot be understood as limiting the protection scope of the present application. Some non-essential improvements and adjustments made by those skilled in the art according to the principles set forth in the present application all belong to the protection scope of the present application. The following examples specifically process parameters are only one example in the appropriate range, that is, those skilled in the art can make appropriate selection within the range through the description herein, and not limited to the specific data of the following examples. The raw materials, reagents or devices used in the following examples and comparative examples can be obtained from conventional commercial channels, or can be obtained by existing known methods, unless otherwise specified.

[0060] Example 1

[0061] A waterborne acrylic coating is prepared by the following method:

[0062] In a dispersing cylinder, water 11.7 parts; pH regulator 0.5 parts; dispersant 0.5 parts; sodium nitrite 0.1 part; waterborne acrylic resin 28 parts; defoaming agent 0.5 parts; pigment 3 parts; filler 54 parts; film forming aid 1.2 parts; thickening agent 0.5 parts are added in sequence. After high-speed stirring, the anti-adhesion waterborne acrylic coating is obtained by filtering with 200 mesh. The pigment-to-binder ratio of the formula is controlled at 4.24.

[0063] Wherein, the pH regulator is N,N-dimethyl ethanolamine (DMEA); the dispersant is Dow's 731a; the defoaming agent is DiGuo's 901W; the waterborne acrylic resin is Rosof's 911 (ROSF-911) purchased from Guangzhou Rosof New Material Technology Co., Ltd., which is a polymer copolymerized by styrene and acrylic ester, and its minimum film forming temperature (MFFT) is 20℃, and solid content is 48wt%; the filler is feldspar powder; the film forming aid is alcohol ester twelve; the thickening agent is Wanhua's U905.

[0064] Example 2

[0065] A waterborne acrylic coating is prepared by the following method:

[0066] In a dispersing cylinder, water 17.8 parts; pH regulator 0.7 parts; dispersant 0.9 parts; sodium nitrite 0.1 part; waterborne acrylic resin 23 parts; defoaming agent 0.9 parts; pigment 1-5 parts; filler 50 parts; film forming aid 1.3 parts; thickening agent 0.3 parts are added in sequence. After high-speed stirring, the anti-adhesion waterborne acrylic coating is obtained by filtering with 200 mesh. The pigment-to-binder ratio of the formula is controlled at 4.98.

[0067] Wherein, the pH regulator is sodium hydroxide; the dispersant is Huihong's 2361; the defoaming agent is Shen Zhu's 6791; the waterborne acrylic resin is Henghe's 2052, whose minimum film forming temperature (MFFT) is 25℃, and solid content is 48wt%; the filler is silicon powder; the film forming aid is propylene glycol phenyl ether (ppH); the thickening agent is Puwei's H120.

[0068] Example 3

[0069] A waterborne acrylic coating is prepared by the following method:

[0070] In a dispersing cylinder, water 16.7 parts; pH regulator 1 part; dispersant 0.7 parts; sodium nitrite 0.1 part; waterborne acrylic resin 25 parts; defoaming agent 0.7 parts; pigment 1 part; filler 53 parts; film forming aid 1.4 parts; thickening agent 0.4 parts are added in sequence. After high-speed stirring, the anti-adhesion waterborne acrylic coating is obtained by filtering with 200 mesh. The pigment-to-binder ratio of the formula is controlled at 4.5.

[0071] Wherein, pH regulator is AMP-95; dispersant is BR85 from Akoma; defoamer is BYK-011, waterborne acrylic resin is 998A from Parchem, its minimum film formation temperature (MFFT) is 20℃, solid content is 48wt%; filler is a mixture of feldspar powder and silica powder, the adding ratio is 1:1; film forming aid is dipropylene glycol butyl ether (DPnB); thickening agent is 12W from Rohm&Haas.

[0072] Comparative Example 1

[0073] A waterborne acrylic coating was prepared by the following method:

[0074] Water 11.2 parts; pH regulator 0.6 parts; dispersant 0.5 parts; sodium nitrite 0.1 part; waterborne acrylic resin 28 parts; defoamer 0.8 parts; pigment 5 parts; filler 52 parts; film forming aid 1.4 parts; thickening agent 0.5 parts were added into a dispersing cylinder in sequence. After high-speed stirring, the waterborne acrylic coating with anti-sticking was obtained by filtering through a 200-mesh screen. The pigment-to-binder ratio of the formulation was controlled at 4.24.

[0075] Wherein, waterborne acrylic resin is 719F from Parchem; pH regulator is sodium hydroxide; dispersant is 4320 from BASF; defoamer is BYK-024 from Dico; waterborne acrylic resin is 719F from Parchem, its minimum film formation temperature (MFFT) is 20℃, solid content is 48wt%; filler is feldspar powder; film forming aid is alcohol ester twelve; thickening agent is U905 from Wanhua.

[0076] The result of Comparative Example 1 was that the emulsion was demulsified, and it was impossible to prepare a uniform liquid coating.

[0077] Comparative Example 1 selected a resin with insufficient powder-encapsulating capacity, and the pigment-to-binder ratio could not reach 4.2 or more. Even if the pigment-to-binder ratio of the formulation was controlled at 4.2 or more, the emulsion was demulsified due to the insufficient powder-encapsulating capacity of the resin, and it was impossible to prepare a liquid coating with a high pigment-to-binder ratio.

[0078] Comparative Example 2

[0079] A waterborne acrylic coating was prepared by the following method:

[0080] Water 6.3 parts; pH regulator 1 part; dispersant 0.8 parts; sodium nitrite 0.1 part; waterborne acrylic resin 35 parts; defoamer 0.9 parts; pigment 4 parts; filler 50 parts; film forming aid 1.4 parts; thickening agent 0.5 parts were added into a dispersing cylinder in sequence. After high-speed stirring, the waterborne acrylic coating with anti-sticking was obtained by filtering through a 200-mesh screen. The pigment-to-binder ratio of the formulation was controlled at 3.2.

[0081] Wherein, the pH regulator is N,N-dimethyl ethanolamine (DMEA); the dispersant is BYK's 2361; the defoaming agent is DEK's 6791; the water-based acrylic resin is Henghe's 2052, whose minimum film forming temperature (MFFT) is 25℃, and solid content is 48wt%; the filler is silicon powder; the film forming aid is propylene glycol phenyl ether (ppH); the thickening agent is Puwei's H120.

[0082] Comparative Example 2 reduces the color base ratio of the formula design, and the color base ratio is controlled to be 3.2.

[0083] Comparative Example 3

[0084] A water-based acrylic paint is prepared by the following method:

[0085] Water 14.8 parts, pH regulator 0.9 parts, dispersant 1 part, sodium nitrite 0.1 part, water-based acrylic resin 26 parts, defoaming agent 0.6 parts, pigment 1 part, filler 54 parts, film forming aid 1.2 parts, and thickening agent 0.4 parts are sequentially added to a dispersion cylinder. After uniform high-speed stirring, the water-based acrylic paint with anti-adhesion is obtained by filtering through a 200-mesh screen. The color base ratio of the formula is controlled to be 4.4.

[0086] Wherein, the pH regulator is AMP-95; the dispersant is Akema's BR85; the defoaming agent is BYK-011; the water-based acrylic resin is Badifu's 998A, whose minimum film forming temperature (MFFT) is 20℃, and solid content is 48wt%; the filler is talc, and the addition ratio is 1:1; the film forming aid is alcohol ester twelve; and the thickening agent is Romenhais's 12W.

[0087] Comparative Example 3 selects the filler talc with a Mohs hardness of 1, and the talc has a mesh number of at least 800 mesh.

[0088] Comparative Example 4

[0089] A water-based acrylic paint is prepared by the following method:

[0090] Water 11.7 parts, pH regulator 0.5 parts, dispersant 0.5 parts, sodium nitrite 0.1 part, water-based acrylic resin 28 parts, defoaming agent 0.5 parts, pigment 3 parts, filler 54 parts, film forming aid 1.2 parts, and thickening agent 0.5 parts are sequentially added to a dispersion cylinder. After uniform high-speed stirring, the water-based acrylic paint with anti-adhesion is obtained by filtering through a 200-mesh screen. The color base ratio of the formula is controlled to be 4.24.

[0091] Wherein, the pH regulator is N,N-dimethyl ethanolamine (DMEA); the dispersant is Dow's 731a; the defoaming agent is Degos' 901W; the water-based acrylic resin is Ross' 911 (ROSF-911) purchased from Guangzhou Ross New Material Technology Co., Ltd., which is a polymer of styrene and acrylic ester copolymer, the minimum film forming temperature (MFFT) of which is 20℃, and the solid content is 48wt%; the filler is barium sulfate; the film forming aid is alcohol ester twelve; and the thickening agent is Wanhua's U905.

[0092] In the comparative example 4, the filler barium sulfate with a Mohs hardness of about 3.5 is selected.

[0093] Comparative example 5

[0094] A water-based acrylic paint is prepared by the following method:

[0095] Water 11.7 parts, pH regulator 0.5 parts, dispersant 0.5 parts, sodium nitrite 0.1 part, water-based acrylic resin 28 parts, defoaming agent 0.5 parts, pigment 3 parts, filler 54 parts, film forming aid 1.2 parts, and thickening agent 0.5 parts are sequentially added into a dispersion cylinder, and then uniformly stirred at high speed, and filtered through a 200-mesh screen to obtain the anti-adhesion water-based acrylic paint. The pigment-to-binder ratio of the formula is controlled to be 4.24.

[0096] Wherein, the pH regulator is N,N-dimethyl ethanolamine (DMEA); the dispersant is Dow's 731a; the defoaming agent is Degos' 901W; the water-based acrylic resin is Ross' 911 (ROSF-911) purchased from Guangzhou Ross New Material Technology Co., Ltd., which is a polymer of styrene and acrylic ester copolymer, the minimum film forming temperature (MFFT) of which is 20℃, and the solid content is 48wt%; the filler is long stone powder; the film forming aid is alcohol ester twelve, and the thickening agent is Rohm & Haas' RM-2020.

[0097] In the comparative example 5, the low-shear thickening agent is replaced by a high-shear thickening agent, and the thickening agent is selected to be Rohm & Haas' RM-2020.

[0098] Comparative example 6

[0099] A water-based acrylic paint is prepared by the following method:

[0100] Water 11.2 parts, pH regulator 0.6 parts, dispersant 0.5 parts, sodium nitrite 0.1 part, water-based acrylic resin 28 parts, defoaming agent 0.8 parts, pigment 5 parts, filler 52 parts, film forming aid 1.4 parts, silicone leveling agent 0.3-0.6, and thickening agent 0.5 parts are sequentially added into a dispersion cylinder, and then uniformly stirred at high speed, and filtered through a 200-mesh screen to obtain the anti-adhesion water-based acrylic paint. The pigment-to-binder ratio of the formula is controlled to be 4.24.

[0101] The water-based acrylic resin is 998A of Bardford; the pH regulator is sodium hydroxide; the dispersing agent is 4320 of BASF; the defoaming agent is BYK-024 of Degao; the water-based acrylic resin is 719F of Bardford, the minimum film forming temperature (MFFT) of which is 20℃, and the solid content is 48wt%; the filler is feldspar powder; the film forming aid is alcohol ester twelve; the silicone leveling agent is BYK-333; and the thickening agent is U905 of Wanhua.

[0102] The comparative example 6 adds a leveling agent.

[0103] Performance test

[0104] 1. Anti-adhesion performance

[0105] There is a national test standard for the anti-adhesion of wood paint, but there is no national test standard for the anti-adhesion of the water-based industrial coating of the present application. According to the test standard of wood paint (GB 1762-1980 Coating Back Sticking Test Method), the formula in the embodiment of the present application is all grade 1, and the discrimination is not high. Therefore, in the specific embodiment of the present application, the test method is improved on the basis of GB 1762-1980, and has a very strong discrimination.

[0106] The test method of GB 1762-1980 Coating Back Sticking Test Method is as follows:

[0107] The coating is prepared on the tinplate according to the brush coating method of “General Coating Preparation Method” (GB 1727-79). After brushing, it is dried for 48 hours under constant temperature and humidity conditions. The filter paper piece is placed on the coating with the smooth surface facing down at a distance of not less than 1 cm from the edge of the sample plate, and the back sticking tester preheated at a temperature of 40±1℃ and a relative humidity of 80±2% is placed in the middle of the filter paper piece, and the temperature and humidity box is closed. Within 5 minutes, the temperature is raised to 40±1℃ and the relative humidity is 80±2%, and the condition is maintained for 10 minutes. The tester is quickly taken out vertically upward, and the sample plate is taken out. After being placed for 15 minutes under constant temperature and humidity conditions, the result is observed with a four-fold magnifying glass.

[0108] The anti-adhesion test method in the specific embodiment of the present application is as follows:

[0109] The substrate is two pieces of cold-rolled steel plates with a size of 15×7×0.1 cm, which are alcohol-washed and then sprayed with water-based acrylic paint prepared by air spraying. The dry film thickness is 60±5μm; then the sample plates are cured at standard conditions for 24h. The two sample plates are stacked together with the side coated with the paint, and placed in a 60℃ air drying oven, and a weight of 5kg is placed on the cold-rolled steel plate; the sample plates are placed at 60℃ for 24h; after 24h, the sample plates are taken out, and then the sample plates are separated using external force, and the area ratio of adhesion is observed and estimated.

[0110] The difference between GB 1762-1980 and the test method in the specific embodiment of the present application mainly lies in that the curing time of the method of the present application is shorter (48 h is changed into 24 h), the mass is heavier (5 kg), the oven temperature is higher (60 DEG C), the contact area is larger (15x7x0.1 cm of cold-rolled steel plate, the adhesion force is larger), and the oven placement time is longer (24 h). Therefore, the test method of the present application is more rigorous, and the adhesion force between the coatings is larger.

[0111] 2, hardness: the hardness of each coating was tested, and the hardness of each coating of the examples was HB.

[0112] The properties of each coating are summarized in Table 1.

[0113] Table 1 Coating properties of examples 1-3 and comparative examples 1-5

[0114]

[0115]

[0116] As shown in Table 1, the water-based acrylic coating of the examples of the present application has good anti-adhesion performance, and can have good anti-adhesion effect even if the hardness is only HB.

[0117] The hardness of the coating in the examples of the present application is improved, not from the perspective of the resin, but from the perspective of the pigment-to-binder ratio and the filler. The hardness of the filler is much larger than that of the resin. Therefore, the pigment-to-binder ratio of the present application is increased to 4.2-5.2, and the filler with a Mohs hardness of 5 or more is selected. The two aspects work together to improve the hardness of the water-based coating and improve the anti-adhesion effect. The hardness of the coating of the present application is HB, which is the hardness limit of the single-component non-modified water-based acrylic coating.

[0118] Furthermore, the examples of the present application construct a rough surface to make the final state of the coating uneven, greatly reducing the contact area when the coatings contact each other, reducing the force between the coatings, and avoiding adhesion and tearing between the coatings. Specifically, the examples of the present application construct a rough surface of the coating in two ways: one is to increase the pigment-to-binder ratio, and the more powder, the rougher the surface of the coating; the other is to use a low shear thickening agent. The low shear thickening agent makes the liquid coating have thixotropy, and the wet film is not flat, and the uneven wet film is uneven.

[0119] The examples of the present application do not add any leveling agent, and the above-mentioned methods work together to make the coating have good anti-adhesion effect even if the hardness is only HB.

[0120] The present application adopts water-based acrylic paint with high pigment-to-binder ratio from the three aspects of improving paint hardness, constructing rough surface and reducing paint cohesion, can effectively improve paint hardness, reduce contact area after coating adhesion, reduce surface force and cohesion, thereby preventing the adhesion of water-based acrylic coating when stacking contact, improving the anti-adhesion effect of water-based acrylic paint, and the water-based acrylic paint has wide application in material protection, especially metal material protection.

Claims

1. A water-based acrylic coating, characterized in that, The preparation materials include the following parts by weight: 18-32 parts waterborne acrylic resin, 0.5-8 parts pigment, 40-65 parts filler, 5-30 parts water, 0.05-0.8 parts thickener, 0.3-1.5 parts dispersant, 0.3-1.5 parts defoamer, and 0.8-1.8 parts film-forming aid; the pigment-to-binder ratio of the coating is 4.2-5.2; the preparation materials do not contain leveling agents. The waterborne acrylic resin includes at least one of Rosef 911, Henghe 2052 or Badifu 998A; The filler has a Mohs hardness of ≥5; the filler includes feldspar powder, silica powder or a combination thereof; The thickener is selected from low-shear thickeners; the low-shear thickener includes at least one of Wanhua U905, Proway H120 or Rohm and Haas 12W.

2. The water-based acrylic coating according to claim 1, characterized in that, The defoamer is selected from polyether-modified silicone defoamers; And / or, the film-forming aid is selected from at least one of alcohol ester dodecyl, propylene glycol phenyl ether, or dipropylene glycol butyl ether.

3. The water-based acrylic coating according to claim 1, characterized in that, The raw materials for preparing the water-based acrylic coating also include pH adjusters, anti-flash rust agents, or combinations thereof.

4. The water-based acrylic coating according to claim 3, characterized in that, The pH adjuster includes at least one of N,N-dimethylethanolamine, 2-amino-2-methyl-1-propanol, or sodium hydroxide. And / or, the anti-flash rust agent is selected from sodium nitrite.

5. The water-based acrylic coating according to claim 1, characterized in that, The preparation materials include the following parts by weight: 18-32 parts waterborne acrylic resin, 0.5-8 parts pigment, 40-65 parts filler, 5-30 parts water, 0.05-0.8 parts thickener, 0.3-1.5 parts dispersant, 0.3-1.5 parts defoamer, 0.8-1.8 parts film-forming aid, 0.3-1.5 parts pH adjuster, and 0.03-0.2 parts anti-flash rust agent.

6. The method for preparing the waterborne acrylic coating according to any one of claims 1 to 5, characterized in that, Includes the following steps: The raw materials are mixed to obtain the water-based acrylic coating.

7. The application of the waterborne acrylic coating according to any one of claims 1 to 5 in material protection.

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