Coating with self-cleaning function and preparation process of color-coated sheet based on coating with self-cleaning function

Abstract

The invention relates to a coating with a self-cleaning function and a color-coated sheet preparation process based on the coating. The coating is prepared from the following components in parts by mass: 4 to 6 parts of nano titanium dioxide, 15 to 20 parts of water, 0.25 to 0.45 part of wetting agent, 0.2 to 0.4 part of thickening agent, 0.3 to 0.7 part of defoaming agent, 0.3 to 0.6 part of cellulose, 0.5 to 2 parts of flatting agent, 12 to 17 parts of coalescing agent and 0.6 to 0.8 part of dispersing agent. According to the invention, on the basis of the coating preparation process of the existing MCM composite color-coated sheet, the steel-plastic-aluminum-plastic composite color-coated sheet is coated with the coating with the specific self-cleaning function and the nano TIO2 plated film through the roller coating process and the VCM laminating process, so that the steel-plastic-aluminum-plastic composite color-coated sheet with the self-cleaning function is prepared, the product function is improved, the production cost is reduced, and the production efficiency is improved. The market demand is met; and the market value is improved. The protective layer can be widely applied to the technical field of color drawing board protective layers.

Description

Technical Field

[0001] The invention belongs to the technical field of color-coated plate protective layer manufacturing, and in particular relates to a coating with a self-cleaning function and a color-coated plate preparation process based on the self-cleaning functional coating. Background Art

[0002] In the process of building decoration, in order to realize the modular decoration of building wall panels, color-coated plates are often used to install the exterior walls of buildings. At the same time, because color-coated plates have strong anti-salt spray performance, strong weather resistance, high strength and light weight, they can be better installed on the exterior walls and are more adaptable to the harsh environment of the building exterior walls.

[0003] However, during the production process of existing color-coated plates, the color-coated plates produced generally do not have a self-cleaning function, which results in the need for manual cleaning of such color-coated plates when used in exterior wall equipment. Summary of the invention

[0004] In view of the above situation, in order to overcome the defects of the prior art, the purpose of the present invention is to provide a coating with self-cleaning function and a preparation process of color-coated plates based on the self-cleaning functional coating, which effectively solves the problem that the existing color-coated plates used in exterior wall buildings do not have self-cleaning function.

[0005] The technical solution to the problem of the present invention is a coating with a self-cleaning function, which includes, by weight, 4-6 parts of nano titanium dioxide, 15-20 parts of water, 0.25-0.45 parts of a wetting agent, 0.2-0.4 parts of a thickener, 0.3-0.7 parts of a defoaming agent, 0.3-0.6 parts of cellulose, 0.5-2 parts of a leveling agent, 12-17 parts of a film-forming aid and 0.6-0.8 parts of a dispersant.

[0006] Among them, nano titanium dioxide, water and cellulose are the most important ingredients.

[0007] Preferably, 0.2-0.6 parts of fungicide are also included.

[0008] A process for preparing a color-coated plate based on a self-cleaning coating comprises the following steps

[0009] Step 1: coating preparation: 4-6 parts of nano titanium dioxide, 15-20 parts of water and 0.3-0.6 parts of cellulose are added into a reaction kettle and stirred and mixed, and 0.25-0.45 parts of a wetting agent, 0.2-0.4 parts of a thickener, 0.3-0.7 parts of a defoaming agent, 0.5-2 parts of a leveling agent, 12-17 parts of a film-forming aid and 0.6-0.8 parts of a dispersant are added in sequence and stirred and mixed, after mixing, the mixture is allowed to stand and 0.2-0.6 parts of a fungicide are added and stirred and mixed to obtain a coating with a self-cleaning function;

[0010] Step 2: Surface treatment of the plate: using alkali solution to treat the surface oil stain of the uncoiled metal and drying it, and passivating the dried metal surface with a passivation solution and drying it to obtain a metal substrate;

[0011] Step 3, coating: coating the coating obtained in step 1 on the surface of the metal substrate obtained in step 2 by roller coating process and cooling the metal substrate coated with the coating by air cooling to obtain a metal substrate with self-cleaning coating;

[0012] Step 4, PE film application: A PET film with sound insulation effect is made by coating the MCM color-coated board with a nano-TiO2 film. The self-cleaning nano-TiO2 film is bonded to the surface of the metal substrate with the self-cleaning coating obtained in step 3 through a VCM bonding process to obtain a color-coated board with a self-cleaning function.

[0013] Preferably, in the step 1, the stirring rate is 1600 r / min, the stirring temperature is 23-25° C., and the standing time is 30 min.

[0014] Preferably, in step 2, the alkali solution is P338 solution, and the passivation solution is chromate passivation solution.

[0015] Preferably, in step 2, the coating amount of the passivation solution is 5 mg / ㎡-8 mg / ㎡, and the drying temperature is 60-80℃.

[0016] Preferably, in step three, the dry film thickness of the coating is 11-13 μm, and the air cooling temperature is 15-20°C.

[0017] The beneficial effects of the present invention are as follows: the present invention uses the existing MCM composite color-coated board coating preparation process to coat the coating with a specific self-cleaning function and the nano-TIO2 plated film on the steel-plastic-aluminum-plastic composite color-coated board through a roller coating process and a VCM bonding process to produce a steel-plastic-aluminum-plastic composite color-coated board with a self-cleaning function, thereby improving product functions, meeting market demands and increasing market value. DETAILED DESCRIPTION

[0018] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by relevant technicians in the field without creative work are within the scope of protection of the present invention.

[0019] Embodiment 1

[0020] Step 1: Coating preparation: 5 parts of nano titanium dioxide, 18 parts of water and 0.45 parts of cellulose were added into a reaction kettle and stirred at 25°C and 1600 r / min for 15 minutes;

[0021] After the stirring is completed, 0.25 parts of a wetting agent, 0.2 parts of a thickener, 0.3 parts of a defoaming agent, 0.5 parts of a leveling agent, 12 parts of a film-forming aid and 0.6 parts of a dispersant are added to the reactor in sequence, and the mixture is stirred and mixed at a stirring rate of 1600 r / min for 15 minutes at 25°C. After the mixing is completed, the mixture is allowed to stand for 30 minutes, and 0.2 parts of a fungicide are added, and the mixture is stirred and mixed at a stirring rate of 1600 r / min for 15 minutes at 25°C to obtain a coating with a self-cleaning function;

[0022] Step 2, plate surface treatment: Use alkaline solution P338 solution to treat the surface oil of the uncoiled metal and dry it, apply chromate passivation solution on the dried metal surface at a coating amount of 5mg / ㎡-8mg / ㎡, passivate the metal surface and dry it in an oven with a drying temperature of 60-80℃, and obtain the metal substrate after drying;

[0023] Step 3, coating: coating the coating obtained in step 1 on the surface of the metal substrate obtained in step 2 by roller coating, the coating having a dry film thickness of 11-13 μm, and cooling the metal substrate coated with the coating by air cooling equipment at an air cooling temperature of 15-18° C., to obtain a metal substrate with a self-cleaning coating;

[0024] Step 4, PE film application: A PET film with sound insulation effect is made by coating the MCM color-coated board with a nano-T IO2 film. The self-cleaning nano-T IO2 film is bonded to the surface of the metal substrate with the self-cleaning coating obtained in step 3 through a VCM bonding process to obtain a color-coated board with a self-cleaning function.

[0025] The roller coating process is to use a three-roller device to apply the coating on one side of the metal substrate. The roller coating process is a common existing technology and will not be introduced in detail here.

[0026] According to GB / T 30191-2013 exterior wall photocatalytic self-cleaning coating material: super hydrophilic contact angle is less than 4°

[0027] According to GB / T13448-2019 test method for color coated steel sheets and strips:

[0028] 1) Pollution resistance: The pollutant is applied and left at room temperature for 72 hours without any change.

[0029] 2) Weather resistance: No significant change after 1000 hours of UVA-340 accelerated aging.

[0030] According to GB / T 9286-2021 cross-cut test for paints and varnishes: 100-grid adhesion level 0.

[0031] According to GB / T9266-2009 Determination of the washability of architectural coatings: Washability: 100 times without damage.

[0032] Embodiment 2

[0033] Step 1: Coating preparation: Add 1 part of nano titanium dioxide, 18 parts of water and 0.45 parts of cellulose into a reaction kettle and stir and mix at a stirring rate of 1600 r / min for 15 minutes at 25°C.

[0034] After the stirring is completed, 0.25 parts of a wetting agent, 0.2 parts of a thickener, 0.3 parts of a defoaming agent, 0.5 parts of a leveling agent, 12 parts of a film-forming aid and 0.6 parts of a dispersant are added to the reactor in sequence, and the mixture is stirred and mixed at a stirring rate of 1600 r / min for 15 minutes at 25°C. After the mixing is completed, the mixture is allowed to stand for 30 minutes, and 0.2 parts of a fungicide are added, and the mixture is stirred and mixed at a stirring rate of 1600 r / min for 15 minutes at 25°C to obtain a coating with a self-cleaning function;

[0035] Step 2, plate surface treatment: Use alkaline solution P338 solution to treat the surface oil of the uncoiled metal and dry it, apply chromate passivation solution on the dried metal surface at a coating amount of 5mg / ㎡-8mg / ㎡, passivate the metal surface and dry it in an oven with a drying temperature of 60-80℃, and obtain the metal substrate after drying;

[0036] Step 3, coating: coating the coating obtained in step 1 on the surface of the metal substrate obtained in step 2 by roller coating, the coating having a dry film thickness of 11-13 μm, and cooling the metal substrate coated with the coating by air cooling equipment at an air cooling temperature of 15-18° C., to obtain a metal substrate with a self-cleaning coating;

[0037] Step 4, PE film application: A PET film with sound insulation effect is made by coating the MCM color-coated board with a nano-T IO2 film. The self-cleaning nano-T IO2 film is bonded to the surface of the metal substrate with the self-cleaning coating obtained in step 3 through a VCM bonding process to obtain a color-coated board with a self-cleaning function.

[0038] According to GB / T 30191-2013 Standard for Photocatalytic Self-cleaning Coating Materials for External Walls, the metal substrate coated with self-cleaning coating is tested: the hydrophilic contact angle is less than 25°

[0039] According to GB / T13448-2019 test method for color coated steel sheets and strips:

[0040] 1) Pollution resistance: The pollutant is applied and left at room temperature for 72 hours without any change.

[0041] 2) Weather resistance: No significant change after 1000 hours of UVA-340 accelerated aging.

[0042] According to GB / T 9286-2021 cross-cut test for paints and varnishes: 100-grid adhesion level 0.

[0043] According to GB / T9266-2009 Determination of the washability of architectural coatings: Washability: 100 times without damage.

[0044] Embodiment 3

[0045] Step 1: Coating preparation: 4 parts of nano titanium dioxide, 15 parts of water and 0.3 parts of cellulose were added into a reaction kettle and stirred at 25°C at a stirring rate of 1600 r / min for 15 minutes;

[0046] After the stirring is completed, 0.25 parts of a wetting agent, 0.2 parts of a thickener, 0.3 parts of a defoaming agent, 0.5 parts of a leveling agent, 12 parts of a film-forming aid and 0.6 parts of a dispersant are added to the reactor in sequence, and the mixture is stirred and mixed at a stirring rate of 1600 r / min for 15 minutes at 25°C. After the mixing is completed, the mixture is allowed to stand for 30 minutes, and 0.2 parts of a fungicide are added, and the mixture is stirred and mixed at a stirring rate of 1600 r / min for 15 minutes at 25°C to obtain a coating with a self-cleaning function;

[0047] Step 2, plate surface treatment: Use alkaline solution P338 solution to treat the surface oil of the uncoiled metal and dry it, apply chromate passivation solution on the dried metal surface at a coating amount of 5mg / ㎡-8mg / ㎡, passivate the metal surface and dry it in an oven with a drying temperature of 60-80℃, and obtain the metal substrate after drying;

[0048] Step 3, coating: coating the coating obtained in step 1 on the surface of the metal substrate obtained in step 2 by roller coating, the coating having a dry film thickness of 11-13 μm, and cooling the metal substrate coated with the coating by air cooling equipment at an air cooling temperature of 15-18° C., to obtain a metal substrate with a self-cleaning coating;

[0049] Step 4, PE film application: A PET film with sound insulation effect is made by coating the MCM color-coated board with a nano-T IO2 film. The self-cleaning nano-T IO2 film is bonded to the surface of the metal substrate with the self-cleaning coating obtained in step 3 through a VCM bonding process to obtain a color-coated board with a self-cleaning function.

[0050] According to GB / T 30191-2013 exterior wall photocatalytic self-cleaning coating materials: super hydrophilic contact angle is less than 10°

[0051] According to GB / T13448-2019 test method for color coated steel sheets and strips:

[0052] 1) Pollution resistance: The pollutant is applied and left at room temperature for 72 hours without any change.

[0053] 2) Weather resistance: No significant change after 1000 hours of UVA-340 accelerated aging.

[0054] According to GB / T 9286-2021 cross-cut test for paints and varnishes: 100-grid adhesion level 0.

[0055] According to GB / T9266-2009 Determination of the washability of architectural coatings: Washability: 100 times without damage.

[0056] Comparative ratio,

[0057] Step 1: Surface treatment of the plate: Use alkaline solution P338 solution to treat the surface oil stain of the uncoiled metal and dry it, apply chromate passivation solution on the dried metal surface at a coating amount of 5mg / ㎡-8mg / ㎡, passivate the metal surface and dry it in an oven with a drying temperature of 60-80℃, and obtain the metal substrate after drying;

[0058] Step 2, PE film application: A PET film with sound insulation effect is made by coating the MCM color-coated board with a nano-T IO2 film. The self-cleaning nano-T IO2 film is bonded to the surface of the metal substrate with the self-cleaning coating obtained in step 3 through a VCM bonding process to obtain a color-coated board with a self-cleaning function.

[0059] According to GB / T 30191-2013 exterior wall photocatalytic self-cleaning coating materials: hydrophilic contact angle is less than 50°

[0060] According to GB / T13448-2019 test method for color coated steel sheets and strips:

[0061] 1) Pollution resistance: The pollutant is applied and left at room temperature for 72 hours without any change.

[0062] 2) Weather resistance: No significant change after 1000 hours of UVA-340 accelerated aging.

[0063] According to GB / T 9286-2021 cross-cut test for paints and varnishes: 100-grid adhesion level 0.

[0064] According to GB / T9266-2009 Determination of the washability of architectural coatings: Washability: 100 times without damage.

[0065] By comparing the above embodiments, it can be intuitively found that by adjusting the ratio between nano-titanium dioxide, water and cellulose in the coating, the hydrophilicity or hydrophobicity of the coating itself can be changed, and the self-cleaning function of the board can be changed by adjusting the hydrophilicity or hydrophobicity. It can be seen from the test data that Example 1 is the most preferred embodiment, and the coating prepared under this ratio can better achieve the self-cleaning performance of the board.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A coating with self-cleaning function, characterized in that: The invention comprises, by weight, 4-6 parts of nano titanium dioxide, 15-20 parts of water, 0.25-0.45 parts of wetting agent, 0.2-0.4 parts of thickener, 0.3-0.7 parts of defoaming agent, 0.3-0.6 parts of cellulose, 0.5-2 parts of leveling agent, 12-16 parts of film-forming aid and 0.6-0.8 parts of dispersant.

2. A coating with self-cleaning function according to claim 1, characterized in that: Also included is 0.2-0.6 parts of fungicide.

3. A process for preparing a color-coated plate based on the coating according to claim 2, characterized in that: The following steps are involved: Step 1: coating preparation: 4-6 parts of nano titanium dioxide, 15-20 parts of water and 0.3-0.6 parts of cellulose are added into a reaction kettle and stirred and mixed, and 0.25-0.45 parts of a wetting agent, 0.2-0.4 parts of a thickener, 0.3-0.7 parts of a defoaming agent, 0.5-2 parts of a leveling agent, 12-17 parts of a film-forming aid and 0.6-0.8 parts of a dispersant are added in sequence and stirred and mixed, after mixing, the mixture is allowed to stand and 0.2-0.6 parts of a fungicide are added and stirred and mixed to obtain a coating with a self-cleaning function; Step 2: Surface treatment of the plate: using alkali solution to treat the surface oil stain of the uncoiled metal and drying it, and passivating the dried metal surface with a passivation solution and drying it to obtain a metal substrate; Step 3, coating: coating the coating obtained in step 1 on the surface of the metal substrate obtained in step 2 by roller coating process and cooling the metal substrate coated with the coating by air cooling to obtain a metal substrate with self-cleaning coating; Step 4, PE film application: A PET film with sound insulation effect is made by coating the nano-TIO2 film on the MCM color-coated board. The self-cleaning nano-TIO2 film is bonded to the surface of the metal substrate with the self-cleaning coating obtained in step 3 through the VCM bonding process to obtain a color-coated board with self-cleaning function.

4. A process for preparing a color-coated plate according to claim 3, characterized in that: In the step 1, the stirring rate is 1600 r / min, the stirring time is 15 min, the stirring temperature is 23-25° C., and the standing time is 30 min.

5. A process for preparing a color-coated plate according to claim 3, characterized in that: In the step 2, the alkali solution is P338 solution, and the passivation solution is chromate passivation solution.

6. A process for preparing a color-coated plate according to claim 3, characterized in that: In the step 2, the coating amount of the passivation solution is 5 mg / ㎡-8 mg / ㎡, and the drying temperature is 60-80℃.

7. A process for preparing a color-coated plate according to claim 3, characterized in that: In the step 3, the dry film thickness of the coating is 11-13 μm, and the air cooling temperature is 15-20° C.