CN115368805B

CN115368805B - Water-based double-component matched paint and preparation method and application thereof

Info

Publication number: CN115368805B
Application number: CN202211149342.0A
Authority: CN
Inventors: 王荣芳; 姚煌; 许奕祥; 谢唯; 王从国
Original assignee: Qingtian Material Technology Co ltd
Current assignee: Qingtian Material Technology Co ltd
Priority date: 2022-09-21
Filing date: 2022-09-21
Publication date: 2024-01-30
Anticipated expiration: 2042-09-21
Also published as: CN115368805A

Abstract

The invention discloses a water-based bi-component matched paint, a preparation method and application thereof, wherein the water-based bi-component matched paint comprises a water-based bi-component primer and a water-based bi-component finish paint; the aqueous double-component primer consists of a specific component A and a specific component B, and the aqueous double-component finish paint consists of a specific component C and a specific component D, wherein the mass ratio of the component A to the component B is 6.5:1-7.5:1, and the mass ratio of the component C to the component D is 8:1-12:1. The water-based bi-component matched paint is not only suitable for large-scale mechanical equipment and wet-on-wet technology, but also can quickly prepare a paint film with environmental protection, smooth surface, good luster, salt spray resistance, boiling resistance, good adhesive force and good initial water drop resistance test performance, and is also suitable for large-scale production.

Description

Water-based double-component matched paint and preparation method and application thereof

Technical Field

The invention relates to the technical field of coatings, in particular to a water-based double-component matched paint and a preparation method and application thereof.

Background

The water drop resistance can well simulate the performance of the material in the environment subjected to rain, so that the material is different from the traditional water boiling resistance (water resistance at 40 ℃), salt fog resistance, adhesive force performance and other related tests.

After the whole large-scale mechanical equipment is assembled, the problems of incomplete spraying, poor durability and the like often exist because of large volume, complex shape of parts, more spraying dead angles and difficult coating. Meanwhile, the paint is easy to contact with corrosion media such as water, gasoline, engine oil, acid and alkali in subsequent operation environments, and strict technical requirements are put forward on the protection performance and the construction performance of the coated water-based protective coating. Meanwhile, in order to meet the higher environmental protection requirement in production, large-scale mechanical equipment manufacturers begin to adopt a two-component composite coating system of an acrylic polyurethane finish paint matched with a water-based epoxy primer and a 2B1C (wet on wet) coating mode with the advantage of cost reduction and efficiency enhancement.

At present, for large-scale mechanical equipment, the large-scale mechanical equipment which is just prepared and has complete unreacted composite coating is usually placed outdoors due to limited production sites and the need of mass preparation of the large-scale mechanical equipment, and the large-scale mechanical equipment just coated has the problem that the large-scale mechanical equipment is difficult to withstand natural environment tests such as sun and rain.

Therefore, development of an aqueous two-component paint which has good water dripping resistance, is suitable for wet-on-wet coating and is suitable for mass production is needed to be very important.

Disclosure of Invention

In order to overcome the problems in the prior art, the invention aims to provide a water-based bi-component matched paint and a preparation method and application thereof.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

in a first aspect, the present invention provides an aqueous two-component kit comprising an aqueous two-component primer and an aqueous two-component topcoat; the water-based double-component primer consists of a component A and a component B, and the water-based double-component finish paint consists of a component C and a component D;

the component A comprises the following raw materials in percentage by mass: aqueous epoxy resin: 35% -45%, first auxiliary agent: 2% -10%, first pigment and filler: 35% -45%, propylene glycol methyl ether: 1% -5%; the component B comprises the following raw materials in percentage by mass: aqueous epoxy curing agent: 60% -70% of propylene glycol methyl ether: 15% -25%; the component C comprises the following raw materials in percentage by mass: aqueous hydroxy acrylic dispersion: 45% -55%, second auxiliary agent: 5% -15% of water-based functional resin: 6% -8%, second pigment and filler: 20% -30%, dipropylene glycol butyl ether: 3% -9%; the component D comprises the following raw materials in percentage by mass: isocyanate curing agent: 75% -82% of propylene glycol diacetate: 15% -22%, dehydrating agent: 1% -5%;

Wherein the mass ratio of the component A to the component B is 6.5:1-7.5:1, and the mass ratio of the component C to the component D is 8:1-12:1.

Specifically, the component A and the component B of the invention select propylene glycol methyl ether with lower boiling point as cosolvent, which not only has good solubility to the aqueous epoxy curing agent in the component B, but also has good dispersibility to the aqueous epoxy resin in the component A, and is beneficial to the mixing and dispersion of the component A and the component B, and the primer can have higher surface drying speed in the later use process, shorten the flash drying time of the wet-on-wet process, and reduce the paint film defects of undercut, miliaria and the like caused by slow drying and non-drying of the primer, thereby having poor water dripping resistance and salt fog resistance.

Preferably, the component A, the component B and the component C further comprise water.

Further preferably, the water in the component A, the component B and the component C is distilled water.

Preferably, the component A comprises the following raw materials in percentage by mass: aqueous epoxy resin: 38% -42%, first auxiliary agent: 4% -8%, first pigment and filler: 38% -42%, propylene glycol methyl ether: 2% -4%, water: 5% -20%;

the component B comprises the following raw materials in percentage by mass: aqueous epoxy curing agent: 60% -70% of propylene glycol methyl ether: 15% -25%, water: 10% -20%;

The component C comprises the following raw materials in percentage by mass: aqueous hydroxy acrylic dispersion: 48% -52%, second auxiliary agent: 6% -12%, aqueous functional resin: 6% -8%, second pigment and filler: 23% -27% of dipropylene glycol butyl ether: 5% -7% of water: 3% -8%;

the component D comprises the following raw materials in percentage by mass: isocyanate curing agent: 75% -82% of propylene glycol diacetate: 15% -22%, dehydrating agent: 1% -5%;

wherein the mass ratio of the component A to the component B is 7:1, and the mass ratio of the component C to the component D is 9:1-10:1.

Preferably, the aqueous epoxy resin in the A component is an aqueous epoxy emulsion.

Preferably, the solid epoxy equivalent in the aqueous epoxy emulsion is 480g/mol to 560g/mol.

Preferably, the solid content in the aqueous epoxy emulsion is 50% -55%.

Preferably, the aqueous epoxy emulsion is selected from one of E-pos1025, PZ 3961, 3EE109W, BC 2060.

Further preferably, the aqueous epoxy emulsion is selected from E-pos1025.

Specifically, E-pos1025 is an aqueous epoxy emulsion of Changzhou full-Rui polymer New Material Co., ltd, the solid content is 50% -55%, the solid epoxy equivalent is 490 g/mol-550 g/mol, and the solid content and solid epoxy equivalent of the aqueous epoxy emulsion of PZ 3961, 3EE109W, BC 2060 are similar to those of E-pos1025, which is advantageous in that the primer exhibits excellent corrosion resistance, quick-drying property and hardness growth property.

Preferably, the first auxiliary agent in the A component consists of a dispersing agent COADIS 123K, a wetting agent DYNOL607, a wetting agent EFKA3772, an antifoaming agent AC-202, a thickening agent RASE-60, a flash rust inhibitor HOS FRI 1203 and a coupling agent MOAP 1316.

Specifically, the dispersing agent COADIS 123K in the component A is COADIS 123K of Coatex company, which is specially modified potassium polycarboxylate, and is a multifunctional hydrophobic high water-resistant dispersing agent. The wetting agent in the component A adopts a mixture of DYNOL607 of American gas chemical products (China) and EFKA3772 of an automobile Epiff card additive, wherein the EFKA3772 belongs to fluorocarbon modified polyacrylic acid and has better leveling effect; DYNOL607 is an acetylenic diol surfactant, has extremely low dynamic surface tension and static surface tension, low level foamability and good compatibility, and has good wetting ability on the substrate of large mechanical equipment parts. The paint film appearance and the coating compactness can be ensured by mixing the paint film and the coating, so that the dripping resistance of the paint film is improved. The defoaming agent in the component A is AC-202 of Lin' an Guanyu special auxiliary agent factory, is a hydrophobic modified mineral oil surfactant, has high-efficiency and durable defoaming performance, and the hydrophobic structure of the defoaming agent is helpful to the water resistance of the coating. The thickening agent in the component A is RASE-60 of Tianjin Sweetcrete chemical industry Co., ltd, is methacrylic acid copolymer emulsion, and has high sagging resistance after being mixed with the water-based epoxy curing agent YG-F300 with the active hydrogen equivalent of 300 in the component B. Therefore, the invention can be demonstrated that proper dispersing agent, wetting agent and defoamer are selected to be used, and the components A with proper viscosity and fluidity can be compounded by the synergistic effect of the components A and the silane coupling agent MOAP 1316 of the flash rust inhibitor HOS FRI 1203 (manufacturer: shanghai lotus industry Co., ltd.) and Shanghai Moire chemical industry Co., ltd.) without nitrite, thus laying a foundation for preparing a matched paint film with good initial water drop resistance in the follow-up process.

Preferably, the mass ratio of the wetting agent DYNOL 607 to the wetting agent EFKA 3772 is 1:1-5:1.

Further preferably, the mass ratio of the wetting agent DYNOL 607 to the wetting agent EFKA 3772 is 2:1.

Preferably, the first pigment and filler in the A-component is composed of bentonite, zinc phosphate, aluminium tripolyphosphate, magnesium silicate, barium sulfate, titanium dioxide, carbon black, iron oxide yellow.

Preferably, the mass ratio of bentonite, zinc phosphate, aluminum tripolyphosphate, magnesium silicate, barium sulfate, titanium dioxide, carbon black and iron oxide yellow is 0.2:6:4:4:20.9:2.2:1.5:1.2.

specifically, the first pigment and the filler in the component A comprise an anti-rust pigment (zinc phosphate and aluminum tripolyphosphate) and a filler (bentonite, magnesium silicate, titanium dioxide barium sulfate, carbon black and iron yellow), and if the dosage of the anti-rust pigment is too small, the ion release concentration is low, and the anti-rust pigment is insufficient to completely passivate a metal substrate to have an anti-corrosion effect or has poor anti-corrosion effect; if the excessive amount of the rust-proof pigment can cause the ion release concentration to be too high, the instability of the system is caused, and meanwhile, the insufficient wetting and wrapping of the resin are easily caused by the excessive amount of the rust-proof pigment, and the overall performance of the system is reduced, so that the amount of the rust-proof pigment is also very critical.

Preferably, the aqueous epoxy curing agent in the component B is an aliphatic polyamine curing agent with an active hydrogen equivalent of 250-350.

Further preferably, the aliphatic polyamine curing agent with the active hydrogen equivalent of 250-350 is YG-F300 of Beijing solar Huider environmental protection technology Co.

Specifically, YG-F300 of Beijing solar Huider environmental protection technology Co., ltd is a nonionic amine curing agent, is an aliphatic polyamine curing agent with an active hydrogen equivalent of 300, is favorable for quick drying of a later-period paint film, and has high crosslinking speed, excellent salt spray resistance and excellent initial water resistance.

Specifically, in the aqueous two-component primer, the increase of the dosage of the aqueous epoxy curing agent in the component B is beneficial to improving the curing speed and the crosslinking density, improving the drying speed and the dripping resistance of a coating film, but as the dosage of the curing agent is increased, excessive curing agent cannot diffuse into the interior of epoxy resin particles to participate in the crosslinking reaction and remain in the coating film to form a hydrophilic medium, so that the dripping resistance and the salt fog resistance of the coating layer are reduced; and the excessive amine curing agent of the primer can be directly reacted with the isocyanate curing agent in the finish paint preferentially, so that the problems of undercut and miliaria of the aqueous polyurethane finish paint are caused, and the water dripping resistance and the salt spray resistance of the composite coating are affected.

Preferably, the aqueous hydroxy acrylic dispersion in the C component is selected from one of YG-AD543, PA-3330, KT-8473, AQUAPAC-8225, antkote 2025.

Further preferably, the aqueous hydroxy acrylic dispersion in component C is AQUAPAC-8225 from Jiangsu Fuqisen New Material Co.

Specifically, AQUAPAC-8225 is an aqueous hydroxyacrylic acid dispersion having a hydroxyl number of 2.5%.

Preferably, the second auxiliary agent in the component C consists of a dispersing agent Addital DX 774, a wetting agent BD-3033, a defoaming agent UNIQ FOAM LP2565, a defoaming agent BYK-028 and a thickening agent Addital WS.

Preferably, the mass ratio of the dispersing agent Addital DX 774 to the wetting agent BD-3033 to the defoaming agent UNIQ FOAM LP2565 to the defoaming agent BYK-028 to the thickening agent Addital WS is 3:2.2:1.5:0.5:0.8.

specifically, the dispersant Addital DX 774, the wetting agent BD-3033, the defoamer UNIQ FOAM LP2565, the defoamer BYK-028 and the thickener Addital WS are all water-based auxiliary agents, so that the water-based paint can play a role in a water-based system, and further the performances of improving the adhesion firmness of the finish paint, resisting water at 40 ℃ and resisting initial water drops and the like under the condition of specific dosage can be improved.

More specifically, the defoaming organosilicon defoamer UNIQ FOAM LP2565 of UKa chemical (Shanghai) limited company in the component C is matched with the FOAM breaking organosilicon defoamer BYK-028 of Pick chemical for use, so that bubbles entrained in a paint film in the production and construction processes are rapidly removed, the integrity of the paint film is ensured, and the drip resistance is improved. The wetting agent in the component C is BD-3033 of Baoer organosilicon Co., hangzhou, and is polyether modified polysiloxane, so that the paint film leveling and glossiness are improved while the surface tension of the paint is reduced. The addition of a large number of component raw materials can lead the functions of different raw materials to be difficult to be exerted, and all raw materials in the component C designed by the invention can act synergistically, so that a paint film prepared by the final paint coating has the advantages of good integrity, good glossiness, salt spray resistance, 40 ℃ water resistance, good initial water dripping resistance and the like.

Preferably, the aqueous functional resin in the C component is YG-HBP075.

Specifically, YG-HBP075 is manufactured by Beijing Naghun Huiden environmental protection technology Co., ltd, is a hyperbranched polymer, has a solid hydroxyl value of 335mgKOH/g-365mgKOH/g, can participate in a crosslinking reaction, and improves the crosslinking density, thereby improving the water resistance and chemical resistance of a paint film.

Preferably, the second pigment and filler in the component C is composed of barium sulfate, titanium dioxide, carbon black, iron oxide yellow.

Preferably, the mass ratio of the barium sulfate to the titanium dioxide to the carbon black to the iron oxide yellow is 20.1:2.2:1.5:1.2.

specifically, the composition of the second pigment and the filler in the component C has certain similarity with the composition of the first pigment and the filler in the component A, and the purpose of the composition and the dosage of the filler are to control the viscosity and the adhesive force of the primer and the finish paint to be similar, so that the primer and the finish paint can be well used together in terms of gloss, color and other functions, and a foundation is laid for the composition of the water-based paint.

Preferably, the isocyanate curing agent in the D component is selected from one of OS-9018, OS-9030, aquolin-269, AQUAPU-360, WT31-100 and X5277.06.

Further preferably, the isocyanate curing agent in the D component is selected from isocyanate X5277.06 of asahi chemical company.

Specifically, isocyanate X5277.06 is hydrophobic aliphatic isocyanate, has stable isocyanurate ring, and can be well dispersed and tightly wrapped in polyurethane polyol particles when used in a formula system of the invention, so that the water-proof performance is good, the drying rate of the finish paint is improved, and the paint film has good water-proof performance in early stage.

Preferably, the dehydrating agent in the D component is BF-5 dehydrating agent.

In a second aspect, the present invention provides a method for preparing the aqueous two-component paint kit according to the first aspect, comprising the steps of:

1) And (3) preparation of the component A: mixing the aqueous epoxy resin, the first auxiliary agent, propylene glycol methyl ether, the first pigment and the filler according to the mass fraction of the first aspect to obtain a component A;

2) And (3) preparation of a component B: mixing the water-based epoxy curing agent and propylene glycol methyl ether according to the mass fraction of the first aspect to obtain a component B;

3) And (3) preparation of a component C: mixing the aqueous hydroxy acrylic dispersion, the second auxiliary agent, the aqueous functional resin, the second pigment, the filler and dipropylene glycol butyl ether according to the mass fraction of the first aspect to obtain a component C;

4) And (3) preparation of a component D: mixing an isocyanate curing agent, propylene glycol diacetate and a dehydrating agent according to the mass fraction of the first aspect to obtain a component D;

5) Mixing the A component and the B component according to the mass ratio of the first aspect to obtain the water-based double-component primer, and mixing the C component and the D component according to the mass ratio of the first aspect to obtain the water-based double-component top coat.

Preferably, the preparation method of the water-based two-component paint kit further comprises the following steps: the ratio of Pigment Volume Concentration (PVC) to Critical Pigment Volume Concentration (CPVC) in the aqueous two-component primer was controlled to be 1.1:1.

specifically, the permeability of a paint film is related to the quality of film formation, and after CPVC is achieved, the water-based double-component primer can be fully wetted and wrapped by pigment and filler particles because of insufficient film forming matters, pores are formed in the paint film, the permeability is rapidly increased, the osmotic pressure difference is gradually reduced, and the foaming tendency during dripping is reduced.

Preferably, the preparation of the component A specifically comprises the following steps:

s1: mixing part of aqueous epoxy resin E-pos1025, water, a dispersing agent COADIS 123K, part of defoaming agent AC-202, a wetting agent DYNOL 607 and propylene glycol methyl ether by stirring to obtain a first mixture;

S2: adding bentonite, zinc phosphate, aluminum tripolyphosphate, magnesium silicate, barium sulfate, titanium dioxide, carbon black and iron oxide yellow into the first mixture, stirring and mixing, and grinding to obtain primer color paste;

s3: mixing the residual aqueous epoxy resin E-pos1025, a wetting agent EFKA 3772, the residual defoaming agent AC-202, a silane crosslinking agent MOAP 1316, a flash rust inhibitor HOS FRI 1203 and a thickening agent RASE-60 with primer color paste in S2 to obtain a component A;

wherein, the added raw materials in S1, S2 and S3 are added according to the mass fraction of the first aspect;

the aqueous epoxy resin E-pos1025 and the defoamer AC-202 were added in two steps, and the mass ratio of the aqueous epoxy resin E-pos1025 in S1 and S3 was 3:5, S1 and S3, wherein the mass ratio of the defoamer AC-202 is 3:1.

preferably, in the preparation process of the component A, the stirring in the step S1 is performed under the condition that the rotating speed is 300 r/min-400 r/min, and the stirring time is 5 min-10 min.

Preferably, in the preparation process of the component A, the stirring in the step S2 is performed under the condition that the rotating speed is 800-1000 r/min, and the stirring time is 10-15 min.

Preferably, during the preparation of the component A, the grinding in the step S2 is specifically to grind the mixture to the particle size of less than 25 μm by using a sand mill at the temperature of 15-45 ℃.

Preferably, during the preparation of the component A, the specific operation of mixing in the step S3 is stirring under the condition of 500 r/min-1000 r/min.

Preferably, the preparation of the component B specifically comprises the following steps: mixing the water-based epoxy hardener YG-F300, the cosolvent PM and water for 5 to 10 minutes at the rotating speed of 300 to 400r/min according to the mass fraction of the first aspect to obtain the component B.

Preferably, the preparation of the component C specifically comprises the following steps:

s1: stirring and mixing part of aqueous hydroxy acrylic acid dispersoid AQUAPC-8225, water, dispersant Addital DX 774, defoamer UNIQ FOAM LP2565 and wetting agent BD-3033 to obtain a second mixture;

s2: adding barium sulfate, titanium dioxide, carbon black and iron oxide yellow into the second mixture, and stirring and grinding to obtain finish paint color paste;

s3: mixing the rest of aqueous hydroxy acrylic acid dispersoid AQUAPAC-8225, aqueous functional resin YG-HBP075, rest of wetting agent BD-3033, defoamer BYK-028, dipropylene glycol butyl ether, thickener Addital WS and finishing paint color paste in S2 to obtain a component C;

The aqueous hydroxy acrylic acid dispersion AQUAPCs-8225 and the wetting agent BD-3033 are added in two steps, and the mass ratio of the aqueous hydroxy acrylic acid dispersion AQUAPCs-8225 in S1 and S3 is 2: the mass ratio of BD-3033 in S1 and S3 is 6:5.

preferably, in the preparation process of the component C, the stirring in the step S1 is performed under the condition that the rotating speed is 300 r/min-400 r/min, and the stirring time is 5 min-10 min.

Preferably, in the preparation process of the component C, the stirring in the step S2 is performed under the condition that the rotating speed is 800-1000 r/min, and the stirring time is 10-15 min.

Preferably, during the preparation of component C, the grinding in S2 is specifically grinding the mixture to a particle size of less than 10 μm using a sand mill at 15-45 ℃.

Preferably, during the preparation of the component C, the specific operation of mixing in the step S3 is stirring under the condition of 500 r/min-1000 r/min.

Preferably, the preparation of the D component specifically comprises the following steps: mixing the isocyanate curing agent X5277.06, propylene glycol diacetate and a dehydrating agent BF-5 for 5-10min at the rotating speed of 300-400 r/min according to the mass fraction of the first aspect to obtain a component D.

In a third aspect, the present invention provides the use of an aqueous two-component paint kit according to the first aspect for the preparation of a coating for large equipment applications.

In a fourth aspect, the present invention provides the use of an aqueous two-component paint according to the first aspect for the preparation of a coating of a metallic or alloy material.

Preferably, the method of application comprises the steps of:

1) Spraying a metal material or an alloy material on the primer in the water-based bi-component matched paint of the first aspect to obtain a material sprayed with the primer;

2) And (3) flashing, spraying finishing paint in the water-based double-component matched paint in the first aspect, leveling, baking and standing the material sprayed with the primer in the step (1) to obtain the material sprayed with the matched primer and the finishing paint.

Preferably, the placing in the step 2) is carried out for 60-120 hours under the conditions that the temperature is 20-25 ℃ and the humidity is 30-85%.

It is further preferred that the placing in step 2) is for 72 hours under the conditions that the temperature is 20 ℃ to 25 ℃ and the humidity is 30% to 85%.

Preferably, the flash-off in step 2) is carried out at a temperature of 25 ℃ and a humidity of 50%.

Preferably, the flash-dry time in the step 2) is 15-25 min.

Preferably, the leveling in the step 2) is performed at a temperature of 20-25 ℃ for 8-15 min.

Preferably, the baking in step 2) is performed at a temperature of 40-60 ℃ and the baking time is 25-30 min.

The beneficial effects of the invention are as follows: the water-based bi-component matched paint is not only suitable for large-scale mechanical equipment and wet-on-wet technology, but also can quickly prepare a paint film with environmental protection, smooth surface, good luster, salt spray resistance, boiling resistance, good adhesive force and good initial water drop resistance test performance, and is also suitable for large-scale production. The method comprises the following steps:

(1) The water-based bi-component matched paint provided by the invention can be used for preparing a composite coating with good water dripping resistance through a short standing time; the specific expression is as follows: the water-based bi-component matched paint can be flash-dried for 20 minutes in an environment with the temperature of 25 ℃ and the humidity of 50% after the primer is sprayed, so that matched finish paint can be sprayed; the surface dry leveling of the finish paint is carried out for 10min at 25 ℃ and baking is carried out for 30min at 40 ℃; then, after being placed for a short time at room temperature (20-25 ℃) and humidity of 30-85% (placing time: 3 hours, the initial dripping resistance test of the material sprayed with the matched paint can pass 168 hours, and the composite coating is not foamed or discolored;

(2) The water-based bi-component matched paint provided by the invention has excellent anti-corrosion performance, and according to the baking condition of (1), after the curing is completed, the neutral salt fog resistance can reach 720 hours, and the water-based bi-component matched paint can provide good appearance and also can provide excellent anti-corrosion capability for large mechanical equipment vehicle parts and other coating substrates;

(3) The water-based bi-component matched paint provided by the invention can be used for preparing paint films with good gloss, impact resistance, strong adhesive force, initial water resistance of not less than 240h, water resistance of not less than 240h at 40 ℃, neutral salt mist resistance of 720h, initial water drip resistance of 168h and other excellent performances by reasonably controlling various components and dosage in a formula and a preparation method.

Detailed Description

The present invention will be described in further detail with reference to specific examples.

In the following examples, "%" is mass fraction unless otherwise specified.

Example 1

The embodiment provides a water-based two-component matched paint, which comprises a primer and a finish, wherein the primer comprises an A component and a B component, and the finish comprises a C component and a D component;

the component A comprises the following raw materials in percentage by mass:

waterborne epoxy E-pos1025:40%;

Dispersant coadi 123K:2%;

defoamer AC-202:0.4%;

wetting agent: 0.3%;

first pigment and filler: 40%;

silane crosslinker MOAP 1316:1.2%;

flash rust inhibitor HOS FRI 1203:1.0%;

thickener RASE-60:0.5%;

propylene glycol methyl ether (i.e., co-solvent PM): 3%;

distilled water: 11.6%;

wherein the wetting agent consists of DYNOL 607 and EFKA 3772, and the mass ratio of DYNOL 607 to EFKA 3772 is 2:1; the pigment comprises, by mass fraction of the first pigment and filler in the A component, 40%, bentonite in the A component of 0.2%, zinc phosphate in the A component of 6%, aluminium tripolyphosphate in the A component of 4%, magnesium silicate in the B component of 4%, barium sulfate in the B component of 20.9%, titanium dioxide in the B component of 2.2%, carbon black in the B component of 1.5% and iron oxide yellow in the B component of 1.2%;

the component B comprises the following raw materials in percentage by mass:

waterborne epoxy curing agent YG-F300:64.3%;

propylene glycol methyl ether (i.e., co-solvent PM): 21%;

distilled water: 14.7%;

wherein the mass ratio of the component A to the component B is 7:1;

the component C comprises the following raw materials in percentage by mass:

aqueous hydroxy acrylic dispersion AQUAPAC-8225:50%;

dispersant Addital DX 774:3.0%;

wetting agent BD-3033:2.2%;

defoamer UNIQ FOAM LP2565:1.5%;

Defoamer BYK-028:0.5%;

aqueous functional resin YG-HBP075:6%;

second pigment and filler: 25%;

thickener Addital WS:0.8%;

dipropylene glycol butyl ether (i.e., co-solvent DPnB): 6%;

distilled water: 5%;

wherein, the weight percent of the first pigment and the filler in the component C is 25 percent, and the pigment and the filler consists of 20.1 percent of barium sulfate, 2.2 percent of titanium dioxide, 1.5 percent of carbon black and 1.2 percent of iron oxide yellow in the component C;

the component D comprises the following raw materials in percentage by mass:

isocyanate curing agent X5277.06:80%;

propylene glycol diacetate (i.e., co-solvent PGDA): 18%;

dehydrating agent BF-5:2%;

wherein the mass ratio of the component C to the component D is 9:1.

In this embodiment, the preparation method of the aqueous two-component paint kit includes the following steps:

(1) Preparing a component A of the aqueous two-component epoxy primer:

s1: under the stirring condition, sequentially adding 15% of aqueous epoxy resin E-pos1025, 11.6% of distilled water, 2% of dispersing agent COADIS 123K, 0.3% of defoamer AC-202, 0.2% of wetting agent DYNOL 607 and 3% of propylene glycol methyl ether (namely cosolvent PM), and stirring and mixing for 5-10min at the rotating speed of 300-400 r/min to obtain a first mixture;

S2, adding 0.2% bentonite, 6% zinc phosphate, 4% aluminum tripolyphosphate, 4% magnesium silicate, 20.9% barium sulfate, 2.2% titanium dioxide, 1.5% carbon black and 1.2% iron oxide yellow into the first mixture, stirring at a rotating speed of 800-1000 r/min for 10-15min, transferring to a sand mill, grinding to a particle size of less than 25 mu m, and controlling the temperature of the mixture in the grinding process to be less than 45 ℃ (namely 15-45 ℃), thus obtaining primer color paste;

s3, uniformly mixing primer color paste in 25% of E-pos1025 resin, 0.1% of wetting agent EFKA 3772, 0.1% of defoamer AC-202, 1.2% of silane cross-linking agent MOAP 1316, 1.0% of flash rust inhibitor HOS FRI 1203, 0.5% of thickener RASE-60 and S2 under the stirring condition of 500-1000r/min to obtain a water-based epoxy primer A component;

(2) Preparing a water-based double-component epoxy primer B component: mixing 64.3% of water-based epoxy hardener YG-F300, 21% of propylene glycol methyl ether (namely cosolvent PM) and 14.7% of distilled water for 5-10min at the rotating speed of 300-400 r/min to obtain a component B;

(3) And (3) preparing a water-based double-component polyurethane finish paint C component:

s1: under the stirring condition, sequentially adding 20% of aqueous hydroxy acrylic acid dispersoid AQUAPC-8225, 5% of distilled water, 3.0% of dispersing agent Addital DX 774, 1.5% of defoamer UNIQ FOAM LP2565 and 1.2% of wetting agent BD-3033, and stirring and mixing at the rotating speed of 300-400 r/min for 5-10min to obtain a second mixture;

S2: adding 20.1% barium sulfate, 2.2% titanium dioxide, 1.5% carbon black and 1.2% iron oxide yellow into the second mixture, stirring and mixing for 10-15min at a rotating speed of 800-1000 r/min, transferring to a sand mill for grinding until the particle size is smaller than 10 mu m, and controlling the temperature of the mixture in the grinding process to be smaller than 45 ℃ (namely 15-45 ℃), thus obtaining finish paint color paste;

s3: uniformly mixing 30% of aqueous hydroxy acrylic acid dispersoid AQUAPAC-8225, 6% of aqueous functional resin YG-HBP075, the rest 1.0% of wetting agent BD-3033, 0.5% of defoamer BYK-028, 6.0% of dipropylene glycol butyl ether (namely cosolvent DPnB), 0.8% of thickener Addital WS and finishing paint color paste in S2 under the stirring condition of 500-1000r/min to obtain aqueous polyurethane finishing paint C component;

(4) And (3) preparing a D component of the aqueous two-component polyurethane finishing paint: stirring and mixing 80% of isocyanate curing agent X5277.06, 18% of cosolvent PGDA and 2% of dehydrating agent BF-5 for 5-10min at a rotating speed of 300-400 r/min to obtain a component D;

(5) Preparation of an aqueous two-component matched paint: mixing the component A and the component B according to the mass ratio of 7:1, and controlling the Pigment Volume Concentration (PVC) of the water-based double-component epoxy primer: critical Pigment Volume Concentration (CPVC) 1.1:1, obtaining the aqueous bi-component epoxy primer; mixing the component C and the component D according to the mass ratio of 9:1 to obtain the aqueous double-component polyurethane finishing paint, wherein the aqueous double-component matched paint is formed by matching an aqueous double-component epoxy primer and an aqueous double-component polyurethane finishing paint.

Example 2

The present example provides a water-based two-component paint kit and a preparation method thereof, and the components and the preparation method in the present example are the same as those in example 1, and the differences from example 1 are only that: the aqueous epoxy resin in this example uses PZ 3961 instead of E-pos1025.

Example 3

The present example provides a water-based two-component paint kit and a preparation method thereof, and the components and the preparation method in the present example are the same as those in example 1, and the differences from example 1 are only that: the waterborne epoxy in this example uses 3EE109W instead of E-pos1025.

Example 4

The present example provides a water-based two-component paint kit and a preparation method thereof, and the components and the preparation method in the present example are the same as those in example 1, and the differences from example 1 are only that: the waterborne epoxy in this example replaced E-pos1025 with BC 2060.

It should be noted that PVC (pigment volume concentration) is related to the pigments in the formulation, and in particular relates to the amount, density, volume and oil absorption of the pigments used, the same type of pigment and filler, the oil absorption of which varies from manufacturer to manufacturer, and finally the amounts of PVC and CPVC (critical pigment volume concentration) vary to achieve the desired PVC, the values of which are controlled by adjusting the type and amount of pigments and fillers.

Comparative example 1

This comparative example provides an aqueous two-component paint kit and a method for preparing the same, the contents of the components and the preparation steps in comparative example 1 are the same as those in example 1, and the difference from example 1 is only that: the barium sulfate dosage in the component A is 16.9%, the distilled water dosage is 15.6%, and the ratio of PVC to CPVC is controlled to be 1.0:1.

comparative example 2

This comparative example provides an aqueous two-component paint kit and a method for preparing the same, and the content of each component and the preparation procedure in comparative example 2 are the same as those in example 1, and the difference from example 1 is only that: the barium sulfate dosage in the component A is 25.9%, the distilled water dosage is 6.6%, and the ratio of PVC to CPVC is controlled to be 1.2:1.

comparative example 3

This comparative example provides an aqueous two-component paint kit and a method for preparing the same, and the content of each component and the preparation procedure in comparative example 3 are the same as those in example 1, and the difference from example 1 is only that: the mass ratio of the component A to the component B in the aqueous two-component epoxy primer is 6:1.

Comparative example 4

This comparative example provides an aqueous two-component paint kit and a method for preparing the same, and the content of each component and the preparation procedure in comparative example 4 are the same as those in example 1, and the difference from example 1 is only that: the mass ratio of the component A to the component B in the aqueous two-component epoxy primer is 8:1.

Comparative example 5

This comparative example provides an aqueous two-component paint kit and a method for preparing the same, and the content of each component and the preparation procedure in comparative example 5 are the same as those in example 1, and the difference from example 1 is only that: the preparation method of the component B is different and specifically comprises the following steps: 43.4% of aqueous epoxy hardener 3EC152W, 21% of cosolvent PM and 35.6% of distilled water are stirred for 5-10min at the rotating speed of 300-400 r/min to obtain the component B.

Comparative example 6

This comparative example provides an aqueous two-component paint kit and a method for preparing the same, and the content of each component and the preparation procedure in comparative example 6 are the same as those in example 1, and the difference from example 1 is only that: the difference between the component C and the component D is specifically: the component C is prepared by replacing 50% of aqueous hydroxy acrylic acid dispersion AQUAPCs-8230 with 50% of aqueous hydroxy acrylic acid dispersion AQUAPCs-8230; the isocyanate curing agent (X5277.06) was used in the D component in an amount of 88%.

The hydroxyl group content of the resin 8230 was 2.9% (mass percent); the hydroxyl value content of the resin 8225 was 2.5% by mass.

Comparative example 7

This comparative example provides an aqueous two-component paint kit and a method for preparing the same, and the content of each component and the preparation procedure in comparative example 7 are the same as those in example 1, and the difference from example 1 is only that: the preparation method of the component D is different and specifically comprises the following steps: 62% of isocyanate curing agent AQUAPU-360, 36% of cosolvent PGDA and 2% of dehydrating agent are stirred for 5-10min at the rotating speed of 300-400 r/min to obtain the component D.

Comparative example 8

This comparative example provides an aqueous two-component paint kit and a method for preparing the same, and the content of each component and the preparation procedure in comparative example 8 are the same as those in example 1, and the difference from example 1 is only that: the preparation method of the component A is different and specifically comprises the following steps: in the preparation of component A, 20% E-pos1025 resin was charged in S1 and 20% PZ 3961 resin was charged in S3.

Comparative example 9

The comparative example provides an aqueous two-component paint kit and a preparation method thereof, and the contents of the components and the preparation steps in comparative example 9 are the same as those in example 1, and the difference from example 1 is that: the preparation method of the component B is different and specifically comprises the following steps: and stirring 32% of the aqueous epoxy hardener YG-F300, 21.7% of the aqueous epoxy hardener 3EC152W, 21% of the cosolvent PM and 25.3% of distilled water for 5-10min at the rotating speed of 300-400 r/min to obtain the component B.

Comparative example 10

This comparative example provides an aqueous two-component paint kit and a method for preparing the same, and the content of each component and the preparation procedure in comparative example 10 are the same as those in example 1, and the difference from example 1 is only that: the difference of the component C is specifically as follows: the amount of the aqueous functional resin YG-HBP075 in the C component is 5.0%.

Comparative example 11

The comparative example provides an aqueous two-component paint kit and a preparation method thereof, the content of each component and the preparation steps in comparative example 11 are the same as those in example 2, and the difference from example 2 is that: the method of performance test was different, and comparative example 11 was left for a longer period of time at the time of performance test (see the performance test section specifically).

Comparative example 11 was set up to demonstrate that the material sprayed with the aqueous two-component kit was allowed to stand for a long period of time (time: 7 d) and the topcoat was substantially completely reacted, and the water drop resistance was enhanced by the masking effect of the paint film, whereas the initial water drop resistance, which is a good water drop resistance in a short period of time after baking of the topcoat when the topcoat was not fully reacted, and the water drop resistance were two different concepts.

In order to visually recognize the difference between example 1 and comparative examples 1 to 11, the respective components in the primers and topcoats in example 1 and comparative examples 1 to 11 are listed in tables 1 and 2, respectively.

TABLE 1 important parameters for the primers in example 1 and comparative examples 1-11

Note that: the first auxiliary agent in table 1 includes a dispersant, a wetting agent, an antifoaming agent, a thickener, a flash rust inhibitor, and a coupling agent in the a-component.

TABLE 2 important parameters for the topcoats of example 1 and comparative examples 1-11

And (3) injection: the second aqueous adjuvants in table 2 include dispersants, wetting agents, defoamers, thickeners in the C-component.

As can be seen from tables 1 and 2: example 1 and comparative examples 1 to 10 are mainly different in the kind or amount of raw materials in the two-component aqueous kit; example 2 and comparative example 11 differ mainly in the extent of reaction of the aqueous composite coating film by controlling the setting time after baking of the top coat.

The raw materials, factories, and product information used in examples 1 to 4 and comparative examples 1 to 11 are shown in table 3 below.

TABLE 3 raw materials, manufacturer and product information used in examples 1 to 4 and comparative examples 1 to 11

/>

As can be seen from table 3: the raw materials used in examples 1 to 4 and comparative examples 1 to 11 are all commercially available reagents, and have the characteristics of convenience and availability, and the formulas and the preparation methods in examples 1 to 4 are indicated to be suitable for industrial production and practical application.

Performance testing

The aqueous two-component epoxy primers and aqueous two-component topcoats prepared in examples 1 to 4 and comparative examples 1 to 11 were prepared and subjected to performance test, and the results are shown in table 4.

The initial drip resistance in table 4 was tested according to the following method, including the following steps:

1) The substrate adopts a cold-rolled common low-carbon steel plate in GB 708-65 rolled sheet steel variety, the size is 150mm multiplied by 70mm multiplied by (0.5-1.2) mm, the surface treatment and the coating of the substrate are carried out according to the spraying method in GB 1727-79 paint film general preparation method, and the substrate sprayed with the primer is obtained;

2) The substrate sprayed with the primer in the step 1) is placed in an environment with the temperature of 25 ℃ and the humidity of 50% to be flash-dried for 20min, then matched finishing paint is sprayed, the finishing paint is controlled to be surface-dried and leveled for 10min at the temperature of 25 ℃, baked for 30min at the temperature of 40 ℃, and then placed at the room temperature (20-25 ℃ and the humidity of 30% -85%) for 3h, and the primer sprayed with the matched primer and the finishing paint is obtained;

3) And (3) receiving distilled water with the height of 3m from a paint film by the substrate sprayed with the matched primer and the finishing paint in the step (2), naturally dripping and impacting according to the frequency of one drop per second, sucking the test board with filter paper for a period of time, immediately checking and recording whether the test board has phenomena of light loss, color change, foaming, wrinkling, rust and the like, recording abnormal time, taking 168h as the longest test time, and recording 168h, thereby indicating that the paint has excellent initial dripping resistance.

The drip resistance in table 4 was tested according to the following method, and the initial drip resistance and the drip resistance were tested by different setting times in step 2), specifically comprising the steps of:

2) The substrate sprayed with the primer in the step 1) is placed in an environment with the temperature of 25 ℃ and the humidity of 50% to be flash-dried for 20min, then matched finishing paint is sprayed, the finishing paint is controlled to be surface-dried and leveled for 10min at the temperature of 25 ℃, baked for 30min at the temperature of 40 ℃, and then placed at the room temperature (20-25 ℃ and the humidity of 30% -85%) for 7h, and the primer sprayed with the matched primer and the finishing paint is obtained;

3) And (3) receiving distilled water with the height of 3m from a paint film by the substrate sprayed with the matched primer and the finishing paint in the step (2), naturally dripping and impacting according to the frequency of one drop per second, sucking the test board with filter paper for a period of time, immediately checking and recording whether the test board has phenomena of light loss, color change, foaming, wrinkling, rust and the like, recording abnormal time, taking 168h as the longest test time, and recording 168h, wherein the test time shows that the paint has excellent dripping resistance.

Table 4 results of Performance test of aqueous two-component epoxy primers and aqueous two-component topcoats prepared in examples 1 to 4, comparative examples 1 to 11

And (3) injection: the appearance characteristics in table 4 were obtained by visual inspection;

gloss is measured by reference to the test standard of GB/T9754-2007, 60% of the tables representing gloss under 60 degree test conditions;

impact properties are measured with reference to the test standard of GB/T1732-1993;

the adhesive force is measured by referring to the test standard of GB/T9286-1998, and the grade 0 is better than the grade I;

the initial water resistance is measured by referring to the test standard of the (A method) in GB/T1733-1993;

the water resistance at 40 ℃ is measured by referring to the test standard of GB/T5209-1985;

initial drip resistance was measured with reference to the methods provided herein;

the neutral salt spray resistance is measured by referring to the test standard of GB/T1771-2007.

As can be seen from table 4:

(1) The paint films in the embodiments 1 to 4 are flat and smooth, have no undercut and prickly heat, and can meet the appearance requirements in the wet-on-wet process;

(2) Although the initial water resistance and 40 ℃ water resistance tests in examples 1 to 4, comparative example 5, comparative example 9, and comparative example 10 are all ∈ 240h, the initial drip resistance results in comparative example 5, comparative example 9, and comparative example 10 are poor, and it can be demonstrated that the initial drip resistance test in the present invention is different from the conventional initial water resistance or 40 ℃ water resistance test;

(3) Example 2 and comparative example 11 are compared, and the dripping resistance of comparative example 11 is superior to that of example 2, and it can be demonstrated that the paint film in the wet-on-wet process has a probability of passing the dripping resistance test by means of a better shielding effect when the paint film is completely reacted, and the initial dripping resistance test in the invention is different from the conventional dripping test;

(4) The paint films of example 1 exhibited excellent properties in terms of initial drip resistance, neutral salt spray resistance and impact resistance as compared with comparative examples 1 to 10, and the effects of examples 2 to 4 were inferior, thereby demonstrating that examples 1 to 4 are each advantageous in obtaining paint films excellent in mechanical properties in winter construction;

(5) According to the performance test result of the example 1, the comprehensive performance of the aqueous two-component matched paint of the example 1 is obviously better than that of the matched paint of the comparative examples 1-10, and the matched two-component paint capable of carrying out wet-on-wet process for large mechanical equipment provided by the invention has the advantages of smooth and smooth paint film appearance, no undercut, high gloss, good impact resistance and adhesive force, and excellent initial water resistance, 40 ℃ water resistance and salt spray resistance. Meanwhile, the paint film in the embodiment 1 has quick drying and excellent initial dripping resistance, so that the paint film can be prepared into a paint film with better quality under a low-temperature baking condition (40 ℃ multiplied by 30 min) in a short time, and a foundation is laid for 'the paint film can be placed in an open air environment for a long time and can keep the integrity of the paint film under the extremely severe environment in which the paint film is not dried (surface drying) and is subjected to rain impact';

(6) When the matched paint is constructed according to the wet-on-wet technology, the primer and the finish paint of the matched paint can be bitten, the paint film is uneven and smooth, the appearance similar to the leveling is poor, the 2C2B construction technology with normal gloss contrast is greatly reduced, the initial water resistance can be shown as bubbling of the paint film in a short time, the water bath resistance at 40 degrees is slightly better than the initial water resistance due to the fact that the paint is according to the test standard, the salt fog performance is caused by the reaction of the finish paint curing agent and the primer curing agent, paint film defects are caused, the phenomena that light loss and bubbling of the panel occur in a short time, the rusting line is corroded to be more than 2mm, and serious even the panel is rusted by flowing. The performance tests listed in the invention can reflect whether a coating is suitable for wet-on-wet process to a certain extent from appearance to performance test.

The above examples are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above examples, and any other changes, modifications, substitutions, combinations, and simplifications that do not depart from the spirit and principle of the present invention should be made in the equivalent manner, and the embodiments are included in the protection scope of the present invention.

Claims

1. A water-based two-component matched paint comprises a water-based two-component primer and a water-based two-component finish paint; the water-based double-component primer consists of a component A and a component B, the water-based double-component finish consists of a component C and a component D, and is characterized in that,

the component A comprises the following raw materials in percentage by mass: aqueous epoxy resin: 38% -42%, a first auxiliary agent: 4% -8%, first pigment and filler: 38% -42%, propylene glycol methyl ether: 2% -4%, water: 5% -11.6%;

the component B comprises the following raw materials in percentage by mass: aqueous epoxy curing agent: 60% -70%, propylene glycol methyl ether: 15% -25%, water: 10% -20%;

the component C comprises the following raw materials in percentage by mass: aqueous hydroxy acrylic dispersion: 48% -52%, a second auxiliary agent: 6% -12% of water-based functional resin: 6% -8%, second pigment and filler: 23% -27% of dipropylene glycol butyl ether: 5% -7% of water: 3% -8%;

the mass ratio of the component A to the component B is 7:1, and the mass ratio of the component C to the component D is 9:1-10:1;

the first pigment and the filler in the component A consist of bentonite, zinc phosphate, aluminum tripolyphosphate, magnesium silicate, barium sulfate, titanium dioxide, carbon black and iron oxide yellow, and the mass ratio of the bentonite, the zinc phosphate, the aluminum tripolyphosphate, the magnesium silicate, the barium sulfate, the titanium dioxide, the carbon black and the iron oxide yellow is 0.2:6:4:4:20.9:2.2:1.5:1.2;

The aqueous hydroxy acrylic acid dispersion in the C component is AQUAPAC-8225, and the aqueous functional resin in the C component is YG-HBP075;

the isocyanate curing agent in the component D is X5277.06;

the aqueous epoxy resin in the component A is E-pos1025;

the aqueous epoxy curing agent in the component B is YG-F300.

2. The aqueous two-component paint kit according to claim 1, wherein: the first auxiliary agent in the component A consists of a dispersing agent COADIS 123K, a wetting agent DYNOL 607, a wetting agent EFKA 3772, an antifoaming agent AC-202, a thickening agent RASE-60, a flash rust inhibitor HOS FRI 1203 and a coupling agent MOAP 1316.

3. The aqueous two-component paint kit according to claim 2, wherein: the mass ratio of the wetting agent DYNOL 607 to the wetting agent EFKA 3772 is 1:1-5:1.

4. The aqueous two-component paint kit according to claim 1, wherein: the second auxiliary agent in the component C consists of a dispersing agent Addital DX 774, a wetting agent BD-3033, a defoaming agent UNIQOAM LP2565, a defoaming agent BYK-028 and a thickening agent Addital WS.

5. A process for the preparation of an aqueous two-component paint kit according to any one of claims 1 to 4, comprising the steps of:

1) And (3) preparation of the component A: mixing the aqueous epoxy resin, the first auxiliary agent, propylene glycol methyl ether, the first pigment and the filler according to the mass fraction of claim 1 to obtain a component A;

2) And (3) preparation of a component B: mixing the water-based epoxy hardener with propylene glycol methyl ether according to the mass fraction of claim 1 to obtain a component B;

3) And (3) preparation of a component C: mixing the aqueous hydroxy acrylic dispersion, the second auxiliary agent, the aqueous functional resin, the second pigment, the filler and dipropylene glycol butyl ether according to the mass fraction of claim 1 to obtain a component C;

4) And (3) preparation of a component D: mixing an isocyanate curing agent, propylene glycol diacetate, a dehydrating agent and dipropylene glycol butyl ether according to the mass fraction of claim 1 to obtain a component D;

5) Mixing the component A and the component B according to the mass ratio of claim 1 to obtain an aqueous two-component primer, and mixing the component C and the component D according to the mass ratio of claim 1 to obtain an aqueous two-component top-coat;

the preparation method of the water-based two-component matched paint further comprises the following steps: the ratio of pigment volume concentration PVC to critical pigment volume concentration CPVC in the aqueous two-component primer was controlled to be 1.1:1.

6. Use of an aqueous two-component paint kit according to any one of claims 1 to 4 for the preparation of a coating for large-scale equipment.

7. Use of an aqueous two-component lacquer according to any one of claims 1 to 4 for the preparation of a coating of a metallic or alloy material.