CN108641505B - Water-based anti-migration and high-weather-resistance fluorocarbon coating and preparation process thereof - Google Patents

Water-based anti-migration and high-weather-resistance fluorocarbon coating and preparation process thereof Download PDF

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CN108641505B
CN108641505B CN201810439159.1A CN201810439159A CN108641505B CN 108641505 B CN108641505 B CN 108641505B CN 201810439159 A CN201810439159 A CN 201810439159A CN 108641505 B CN108641505 B CN 108641505B
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water
agent
percent
migration
weather
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CN108641505A (en
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璧典附
赵丽
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Zhengzhou Xinyang New Material Technology Co ltd
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Zhengzhou Xinyang New Material Technology Co ltd
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    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D127/00Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Coating compositions based on derivatives of such polymers
    • C09D127/02Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Coating compositions based on derivatives of such polymers not modified by chemical after-treatment
    • C09D127/12Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Coating compositions based on derivatives of such polymers not modified by chemical after-treatment containing fluorine atoms
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2205/00Polymer mixtures characterised by other features
    • C08L2205/03Polymer mixtures characterised by other features containing three or more polymers in a blend
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2312/00Crosslinking

Abstract

The invention discloses a water-based anti-migration and high-weather-resistance fluorocarbon coating and a preparation process thereof, wherein the coating is prepared from the following components in percentage by mass: 40-80% of water-based fluorocarbon resin, 5-15% of cross-linked resin, 0.2-0.6% of dispersing agent, 0.1-0.8% of base material wetting agent, 0.1-0.6% of flatting agent, 0.2-0.8% of defoaming agent, 2-10% of water-based polyester resin, 0-5% of flatting agent, 15-25% of deionized water, 0.6-1% of thickening agent, 0.1-0.5% of bactericide and 0.1-0.5% of pH regulator. The water-based anti-migration and high-weather-resistance fluorocarbon coating provided by the invention is high in crosslinking density, good in anti-migration performance and low in VOC content, is a single-component coating, and solves the problems that the existing baking varnish is short in working life, not suitable for assembly line operation with long pause and large yield in the production process.

Description

Water-based anti-migration and high-weather-resistance fluorocarbon coating and preparation process thereof
Technical Field
The invention relates to the technical field of coatings, in particular to a water-based anti-migration and high-weather-resistance fluorocarbon coating and a preparation process thereof.
Background
With the improvement of the requirements of people on product packaging and decoration, the transfer printing technology develops rapidly, and the currently popular transfer printing technology with wider application range is thermal transfer printing and water transfer printing. After transfer printing, a clear coat is usually sprayed on the transfer printing layer. Therefore, when the transfer printing technology is rapidly developed, the dosage of the clear finish paint is increased, and at present, the clear finish paint is still mainly solvent-based, wherein the VOC content is more than 60 percent, and the clear finish paint further contains a large amount of benzene series. In recent years, the environmental protection pressure is increased, some enterprises replace the water-based acrylic acid amino baking paint and the water-based alkyd amino baking paint, the benzene series is relatively controlled, but in order to better keep the water solubility, a large amount of organic cosolvent is inevitably added, the actual VOC is higher, and meanwhile, the problems of large smell, poor weather resistance, poor migration resistance and the like are caused to the water-based acrylic acid baking paint and the water-based alkyd baking paint in different degrees in the application process, so that great troubles are brought to downstream customers, and great obstacles are brought to the popularization and application of the water-based paint. The market is in urgent need to develop a low-VOC, high-weather-resistance and anti-migration aqueous product.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a paint which is based on aqueous fluorocarbon resin, is migration-resistant, high in weather resistance and low in VOC content.
The purpose of the invention is realized by the following technical scheme:
the water-based anti-migration and high-weather-resistance fluorocarbon coating is prepared from the following components in percentage by mass:
the aqueous fluorocarbon resin is FEVE aqueous fluorocarbon emulsion with an alternating copolymerization structure formed by utilizing a phase inversion emulsification technology.
A preparation process of a water-based anti-migration and high-weather-resistance fluorocarbon coating comprises the following steps:
1) slowly adding the aqueous fluorocarbon emulsion in the formula into a paint mixing tank, adding the dispersing agent and the defoaming agent under the stirring state of 300r/min, and then stirring at the speed of 500r/min for dispersing for 10-30 min;
2) slowly adding the flatting agent under the stirring state of 300r/min, then slowly increasing the speed, after the flatting agent is completely soaked, increasing the speed to 1300r/min, stirring for 25-35min, testing by using a scraper fineness meter, and stopping when the fineness is less than 15 mu m;
3) slowly adding the cross-linked resin, the deionized water, the flatting agent, the base material wetting agent, the pH regulator, the water-based polyester resin and the bactericide under stirring at 300r/min, dispersing for 15-30min, adding the thickening agent, adjusting the viscosity to 45-65s, filtering and packaging to obtain the finished product.
The aqueous fluorocarbon resin used in the invention is FEVE aqueous fluorocarbon emulsion with an alternating copolymerization structure formed by utilizing a phase inversion emulsification technology, and the product has high crosslinking density, good weather resistance and low VOC content. The waterborne polyester resin in the components can enhance the adhesive force of a coating film on different base materials, such as stainless steel, aluminum materials and the like, can improve the compactness of the coating film, and has the hardness of more than 3H, the water resistance of more than 60 days, 10% sulfuric acid resistance of 35 days, 10% sodium hydroxide resistance of 35 days and butanone wiping resistance of 200 times without change.
The water-based anti-migration and high-weather-resistance fluorocarbon coating provided by the invention is a single-component coating, is in flow line operation during coating, is convenient to construct, enters a drying tunnel after being sprayed for forced drying at 150-160 ℃/30min, and is subjected to a crosslinking reaction only when reaching a curing temperature, so that a three-dimensional network structure is finally formed, and the requirements of a coating with high decoration and high durability are met; water is used as a diluent, so that almost no VOC exists; the coating has high fluorine content, about 20 percent of fluorine content and good weather resistance, simultaneously overcomes the problem of transfer printing ink migration phenomenon of a bottom layer, can effectively prolong the service life of the coating, improves the economic benefit, is particularly suitable for protection of substrates after heat transfer printing and water transfer printing, and the like, such as the anti-theft door industry, and is suitable for steel anti-theft doors, window decoration and outer surface protection.
Compared with the prior art, the invention has the following beneficial effects:
(1) the water-based anti-migration and high-weather-resistance fluorocarbon coating provided by the invention has high crosslinking density and good migration resistance, is improved by more than 40% in weather resistance compared with the water-based acrylic amino baking paint widely used in the anti-theft door industry, is improved by 50% in migration resistance, and has good storage stability;
(2) the water-based anti-migration and high-weather-resistance fluorocarbon coating provided by the invention has low VOC content, the VOC can be controlled below 30g/L during construction through testing, tap water is used for directly varnishing equipment after construction, no VOC is generated, and the VOC of similar solvent-based fluorocarbon coatings reaches more than 60%, so that the environment is greatly damaged;
(3) the water-based anti-migration and high-weather-resistance fluorocarbon coating provided by the invention is a single-component coating, is in flow line operation during coating, is convenient to construct, enters a drying tunnel for forced drying after spraying, and solves the problems that the existing two-component baking paint has short working life (2-3 h of the two-component water-based paint and 3-6h of the two-component oily paint after blending), is not suitable for long-pause and high-yield flow line operation in the production process.
Detailed Description
To further illustrate the technical means and effects of the present invention, the following detailed description is given with reference to specific embodiments.
Example 1
The water-based anti-migration and high-weather-resistance fluorocarbon coating is prepared from the following components in percentage by mass:
a preparation process of a water-based anti-migration and high-weather-resistance fluorocarbon coating comprises the following steps:
1) slowly adding the aqueous fluorocarbon emulsion in the formula into a paint mixing tank, adding the dispersing agent and the defoaming agent under the stirring state of 300r/min, and then stirring at the speed of 500r/min for dispersing for 10 min;
2) slowly adding the flatting agent under the stirring state of 300r/min, then slowly increasing the speed, after the flatting agent is completely soaked, increasing the speed to 1300r/min, stirring for 25min, testing by using a scraper fineness meter, and stopping when the fineness is less than 15 mu m;
3) slowly adding the cross-linked resin, the deionized water, the flatting agent, the base material wetting agent, the pH regulator, the water-based polyester resin and the bactericide under stirring at 300r/min, dispersing for 15min, adding the thickening agent, adjusting the viscosity to 45s, filtering and packaging to obtain a finished product.
Example 2
The water-based anti-migration and high-weather-resistance fluorocarbon coating is prepared from the following components in percentage by mass:
a preparation process of a water-based anti-migration and high-weather-resistance fluorocarbon coating comprises the following steps:
1) slowly adding the aqueous fluorocarbon emulsion in the formula into a paint mixing tank, adding the dispersing agent and the defoaming agent under the stirring state of 300r/min, and then stirring at the speed of 500r/min for dispersing for 15 min;
2) slowly adding the flatting agent under the stirring state of 300r/min, then slowly increasing the speed, after the flatting agent is completely soaked, increasing the speed to 1300r/min, stirring for 30min, testing by using a scraper fineness meter, and stopping when the fineness is less than 15 mu m;
3) slowly adding the cross-linked resin, the deionized water, the flatting agent, the base material wetting agent, the pH regulator, the water-based polyester resin and the bactericide under stirring at 300r/min, dispersing for 20min, adding the thickening agent, adjusting the viscosity to 50s, filtering and packaging to obtain a finished product.
Example 3
The water-based anti-migration and high-weather-resistance fluorocarbon coating is prepared from the following components in percentage by mass:
the aqueous fluorocarbon resin is FEVE aqueous fluorocarbon emulsion with an alternating copolymerization structure formed by utilizing a phase inversion emulsification technology.
A preparation process of a water-based anti-migration and high-weather-resistance fluorocarbon coating comprises the following steps:
1) slowly adding the aqueous fluorocarbon emulsion in the formula into a paint mixing tank, adding the dispersing agent and the defoaming agent under the stirring state of 300r/min, and then stirring at the speed of 500r/min for dispersing for 25 min;
2) slowly adding the flatting agent under the stirring state of 300r/min, then slowly increasing the speed, after the flatting agent is completely soaked, increasing the speed to 1300r/min, stirring for 32min, testing by using a scraper fineness meter, and stopping when the fineness is less than 15 mu m;
3) slowly adding the cross-linked resin, the deionized water, the flatting agent, the base material wetting agent, the pH regulator, the water-based polyester resin and the bactericide under stirring at 300r/min, dispersing for 25min, adding the thickening agent, adjusting the viscosity to 60s, filtering and packaging to obtain a finished product.
Example 4
The water-based anti-migration and high-weather-resistance fluorocarbon coating is prepared from the following components in percentage by mass:
a preparation process of a water-based anti-migration and high-weather-resistance fluorocarbon coating comprises the following steps:
1) slowly adding the aqueous fluorocarbon emulsion in the formula into a paint mixing tank, adding the dispersing agent and the defoaming agent under the stirring state of 300r/min, and then stirring at the speed of 500r/min for dispersing for 30 min;
2) slowly adding the flatting agent under the stirring state of 300r/min, then slowly increasing the speed, after the flatting agent is completely soaked, increasing the speed to 1300r/min, stirring for 35min, testing by using a scraper fineness meter, and stopping when the fineness is less than 15 mu m;
3) slowly adding the cross-linked resin, the deionized water, the flatting agent, the base material wetting agent, the pH regulator, the water-based polyester resin and the bactericide under stirring at 300r/min, dispersing for 30min, adding the thickening agent, adjusting the viscosity to 65s, filtering and packaging to obtain a finished product.
Comparative example 1
Commercially available aqueous acrylic amino stoving enamels.
Comparative example 2
Commercially available waterborne alkyd amino stoving enamels.
Performance testing
The products obtained in examples 1-4 and comparative examples were tested for performance and the results are shown in Table 1.
TABLE 1
As can be seen from Table 1, the coatings prepared in examples 1-4 all have better properties than comparative examples 1 and 2.
Environmental protection test
The products obtained in examples 1-4 and comparative examples were tested for performance and the results are shown in Table 2.
TABLE 2
As can be seen from Table 2, the VOC value of the coating prepared in the embodiment 1-4 is far lower than that of the coating prepared in the comparative example 1 and the coating prepared in the comparative example 2, and the coating does not contain harmful substances such as formaldehyde, benzene, toluene and heavy metals, so that the coating has obvious environmental protection advantage and is worthy of popularization.
The above description is only for the specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto, and other modifications or equivalent substitutions made by the technical solution of the present invention by the ordinary skilled in the art should be covered within the scope of the claims of the present invention without departing from the spirit and scope of the technical solution of the present invention.

Claims (2)

1. The water-based anti-migration and high-weather-resistance fluorocarbon coating is prepared from the following components in percentage by mass:
40-80% of water-based fluorocarbon resin,
5 to 15 percent of cross-linked resin,
0.2 to 0.6 percent of dispersant,
0.1 to 0.8 percent of base material wetting agent,
0.1 to 0.6 percent of flatting agent,
0.2 to 0.8 percent of defoaming agent,
2 to 10 percent of water-based polyester resin,
0 to 5 percent of flatting agent,
15 to 25 percent of deionized water,
0.6 to 1 percent of thickening agent,
0.1 to 0.5 percent of bactericide,
0.1 to 0.5 percent of pH regulator;
the aqueous fluorocarbon resin is FEVE aqueous fluorocarbon emulsion with an alternating copolymerization structure formed by utilizing a phase inversion emulsification technology.
2. The preparation process of the waterborne migration-resistant and high-weather-resistant fluorocarbon coating according to claim 1, characterized by comprising the following steps:
1) slowly adding the aqueous fluorocarbon emulsion in the formula into a paint mixing tank, adding the dispersing agent and the defoaming agent under the stirring state of 300r/min, and then stirring at the speed of 500r/min for dispersing for 10-30 min;
2) slowly adding the flatting agent under the stirring state of 300r/min, then slowly increasing the speed, after the flatting agent is completely soaked, increasing the speed to 1300r/min, stirring for 25-35min, testing by using a scraper fineness meter, and stopping when the fineness is less than 15 mu m;
3) slowly adding the cross-linked resin, the deionized water, the flatting agent, the base material wetting agent, the pH regulator, the water-based polyester resin and the bactericide under stirring at 300r/min, dispersing for 15-30min, adding the thickening agent, adjusting the viscosity to 45-65s, filtering and packaging to obtain the finished product.
CN201810439159.1A 2018-05-09 2018-05-09 Water-based anti-migration and high-weather-resistance fluorocarbon coating and preparation process thereof Active CN108641505B (en)

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