1. The water-based steel drum coating is characterized in that: the paint at least comprises the following components in parts by weight:

45-55 parts of acrylic emulsion;

35-38 parts of color paste;

1-3 parts of self-made epoxy phosphate;

0.1-0.2 parts of wetting agent;

3-5 parts of amino resin;

3-6 parts of dipropylene glycol methyl ether;

0.2-0.6 part of leveling agent;

3-6 parts of deionized water;

0.05 to 0.15 portion of closed aqueous catalyst.

2. The water-based steel drum paint as claimed in claim 1, wherein: the paint comprises the following components in parts by weight:

41.22 parts of acrylic emulsion;

8.2 parts of epoxy modified acrylic resin;

36.71 parts of color paste;

1.41 parts of self-made epoxy phosphate;

0.11 part of wetting agent;

0.71 part of thickening agent;

3.53 parts of amino resin;

3.53 parts of dipropylene glycol methyl ether;

0.28 part of leveling agent;

3.77 parts of deionized water;

0.07 part of closed aqueous catalyst.

3. The water-based steel drum paint as claimed in claim 1, wherein: the paint comprises the following components in parts by weight:

49.42 parts of acrylic emulsion;

36.71 parts of color paste;

1.41 parts of self-made epoxy phosphate;

0.11 part of wetting agent;

0.71 part of thickening agent;

3.53 parts of amino resin;

3.48 parts of dipropylene glycol methyl ether;

0.28 part of leveling agent;

3.53 parts of deionized water;

0.11 part of closed aqueous catalyst.

4. The water-based steel drum paint as claimed in claim 1, wherein: the paint comprises the following components in parts by weight:

49.42 parts of acrylic emulsion;

36.71 parts of color paste;

1.41 parts of self-made epoxy phosphate;

0.11 part of wetting agent;

4.73 parts of amino resin;

3.53 parts of dipropylene glycol methyl ether;

0.28 part of leveling agent;

3.53 parts of deionized water;

0.05 part of water-based catalyst is sealed.

5. The water-based steel drum paint as claimed in claim 1, wherein: the color paste comprises the following components in parts by weight:

12-15 parts of self-made epoxy modified acrylic resin;

5-9 parts of ethylene glycol butyl ether;

0.05-0.1 part of DMEA;

0.1-0.5 part of wetting agent;

0.1-0.5 part of defoaming agent;

1-2 parts of a dispersion aid;

3-5 parts of a pigment dispersant;

20-30 parts of deionized water;

15-19 parts of titanium dioxide;

25-30 parts of toner;

the pigment dispersant was zetasperse3800 pigment dispersant.

6. The water-based steel drum paint as claimed in claims 1-4, wherein: the acrylic emulsion is Wanhuaantkote 2083 acrylic emulsion, the amino resin is Zhanxin Cymel 303, the closed water-based catalyst is Nacure 5925, the wetting agent is winning TEGO WET 872, and the leveling agent is winning 420 leveling agent.

7. The preparation process of the water-based steel barrel paint according to any one of claims 1 to 5, wherein the preparation process comprises the following steps: the method comprises the following steps:

s1: preparing epoxy modified acrylic resin;

s2, preparing epoxy phosphate;

s3: preparing color paste: mixing the epoxy modified acrylic resin prepared in the step S1, ethylene glycol monobutyl ether, a DMEA neutralizer, a defoaming agent, an auxiliary dispersing agent, a pigment dispersing agent, deionized water, titanium dioxide and toner according to the proportion of claim 5, placing the mixture into a high-speed dispersion machine to disperse for 30 minutes at the rotating speed of 900-1100 r/min, and placing the mixture into a sand mill to grind for 40 minutes under a cooling state to form a red pigment with the particle size of less than 6 microns;

s4: proportioning according to the proportion: weighing and proportioning the acrylic emulsion, the color paste, the epoxy phosphate prepared in the step S2, the wetting agent, the thickening agent, the amino resin, the dipropylene glycol methyl ether, the leveling agent, the deionized water and the closed water catalyst according to the proportion in the claim 1;

s5, stirring and mixing: stirring the material proportioned according to the S4 at the rotating speed of 200 and 500 revolutions of a high-speed dispersion machine for more than 30 minutes at room temperature, filtering, detecting and packaging to obtain the water-based steel barrel coating.

8. The preparation process of the water-based steel barrel paint as claimed in claim 7, wherein the preparation process comprises the following steps: the preparation process of the self-made epoxy modified acrylic resin in the step S1 is as follows:

s11: preparing a base material: preparing 15-20 parts of ethylene glycol butyl ether, dissolving 35-45 parts of Nantong star 901 solid epoxy resin into an epoxy solution, adding 18-30 parts of acrylic acid monomer, and mixing to obtain a base material for later use;

s12: preparing a monomer mixed solution: mixing 17-30 parts of styrene, 45-65 parts of butyl acrylate, 5-15 parts of methyl methacrylate, 1-5 parts of hydroxypropyl acrylate, 3-5 parts of tert-butyl peroxy-2-ethylhexanoate (TBPO) initiator and 10-20 parts of propylene glycol methyl ether solvent to prepare a mixed solution;

s13: preparing other materials: 0.2-1.0 part of tert-butyl peroxy-2-ethylhexanoate (TBPO) initiator, 0.2-1.0 part of propylene glycol methyl ether solution as complementary initiator, 6-16 parts of n-butanol, 20-40 parts of ethylene glycol butyl ether as diluent, and 2.2-3.6 parts of dimethylethanolamine as neutralizer

S14: stirring and mixing:

s141: heating the base material prepared in the step S11 to 95-100 ℃ under the stirring state;

s142: uniformly dropwise adding the mixed solution prepared in the step S12 into the stirred and heated base material within 3 hours, controlling the temperature to be 95-100 ℃, and preserving heat for 1 hour after dropwise adding;

s143: uniformly dropwise adding the tert-butyl peroxy-2-ethylhexanoate (TBPO) initiator prepared in the step S13 and the propylene glycol methyl ether solution into the material prepared in the step S14.2 for 0.5 hour, and preserving heat for 2.5-3 hours at the temperature of 95-100 ℃ after dropwise adding;

s144: after the heat preservation is finished, cooling to 70 ℃, adding the n-butyl alcohol, the ethylene glycol butyl ether and the dimethylethanolamine prepared in the step S13, stirring uniformly, continuously cooling to below 50 ℃, filtering and packaging for later use;

the water-soluble epoxy modified acrylic resin is prepared by the above process.

9. The preparation process of the water-based steel barrel paint as claimed in claim 7, wherein the preparation process comprises the following steps: the preparation process of the self-made epoxy phosphate in the step S2 is as follows:

s21: preparing an epoxy solution: heating 3.0-5.0 parts of ethylene glycol monobutyl ether and 7-10 parts of Nantong star 850S epoxy resin to 45 ℃ under the stirring state, and dissolving to prepare an epoxy solution;

s22, pre-dissolving: dissolving 0.6-1.2 parts of 85% phosphoric acid, 0.2-1.0 part of deionized water and 0.2-1.0 part of butyl cellosolve at room temperature in advance;

s23, preparing other materials: preparing 2.2-7.0 parts of ethylene glycol butyl ether and 0.6-1.6 parts of dimethylethanolamine;

s24: phosphorization:

s241: adding the material pre-dissolved in the step S22 into the epoxy solution prepared in the step S21, heating to 60 ℃, preserving heat for 1 hour, then heating to 100-110 ℃ within 1 hour, and preserving heat for 3 hours;

s242: adding 2.0-5.0 parts of butyl cellosolve and cooling to 50 ℃;

s243: adding 0.6-1.6 parts of dimethylethanolamine and 0.2-2.0 parts of ethylene glycol monobutyl ether and ethylene glycol monobutyl ether, and uniformly stirring to prepare the water-soluble epoxy phosphate resin.

10. The method of applying an aqueous steel drum paint according to any one of claims 1 to 9, wherein: for coating the surface of a steel drum, comprising the following steps:

s1: feeding iron: opening the whole sheet package, conveying the sheet package to the front section of the production line by a forklift, placing the sheet package on a pinch roll, and continuously and sequentially conveying the iron plates to a pretreatment working section in a magnetic suction mode;

s2: pretreatment: deoiling and degreasing a metal plate by using special treatment liquid, carrying out spray cleaning, then passivating by using passivation liquid, and heating and drying the metal plate;

s3: and (3) roller coating: the method comprises the following steps of (1) adsorbing a metal plate by magnetic force, placing the metal plate on a conveying chain, placing a water-based paint in a trough in advance, coating the metal plate twice through a rubber roll, and immediately coating the metal plate with the water-based paint for the second time without baking after the first time of coating;

s4: baking: the coated metal plate enters a tunnel type drying room through a conveying line at the speed of 30-40 sheets/min;

setting the baking temperature of the drying room to be 140 ℃ at the front section, 140 ℃ at the middle section and 170 ℃ at the rear end, and controlling the panel to pass through the rear end constant temperature area for 3-5 minutes;

s5: and (3) cooling: then cooling the plate by air blast;

s6: receiving: the metal sheets are stacked orderly through a material receiving machine;

s7: barrel making: and (5) cutting, rolling, carrying out resistance welding on the sheet in the step S4, coating welding seam paint, sealing the upper cover and the lower cover, and finally manufacturing the packaging barrel.

Background

The steel drum is a container which is used for containing gasoline, diesel oil and various chemical raw materials in the industrial field, and has the characteristics of large volume, high strength, difficult damage, convenient transportation and the like, so the steel drum is accepted by various enterprises. Meanwhile, in order to clarify the properties of the materials contained in the steel drum and protect the steel drum, steel drum manufacturers often coat protective paint on the surface of the steel drum.

With the increasing attention of people to the environmental problems, environmental regulations are becoming stricter, and various environmental regulations have strict limits on the emission of Volatile Organic Compounds (VOC), organic solvents and the content of various heavy metals. Green and environment-friendly coatings have become a trend in the development of the coating industry.

The metal baking paint is an industrial paint which is widely applied, and a plurality of metal products are coated with the metal baking paint on the surface to play the roles of protection and decoration. The traditional baking varnish coating has low price, bright and hard coating film and strong adhesive force, and is commonly used in the industries of mechanical manufacturing, electromechanics, hardware and the like. However, the traditional baking varnish baking has the defects of high temperature, long drying time, high energy consumption, poor toughness and the like, and the storage period is short; the traditional baking varnish mostly uses organic solvent as solvent, which is obviously unfavorable for increasingly strict environmental requirements, and the adhesion force of the existing steel barrel protective varnish to the metal surface is often weak, and peeling is easy to occur after impact, therefore, the protection time of the steel barrel is generally short, in order to achieve the protection effect, multi-layer coating is often required to be coated, the existing coating is poor in flatness and bonding force, and the defects of air bubbles, leveling and the like caused by uneven baking are often avoided by baking after coating the coating every time, energy is not enough saved, and long time is required to be consumed, meanwhile, the coating mode of the external coating of the steel barrel at present mainly adopts a mode of firstly preparing the barrel and then spraying, but the problems of uneven coating, coating waste and the like easily occur in spraying and coating.

Disclosure of Invention

Therefore, in order to solve the problems and realize the purposes, the invention provides the water-based steel barrel coating, the preparation process and the application.

The invention is realized by the following technical scheme:

the water-based steel drum coating at least comprises the following components in parts by weight:

preferably, the composition comprises the following components in parts by weight:

preferably, the composition comprises the following components in parts by weight:

preferably, the composition comprises the following components in parts by weight:

preferably, the color paste comprises the following components in parts by weight:

the pigment dispersant was zetasperse3800 pigment dispersant.

Preferably, the acrylic emulsion is a Wanhuaantkote 2083 acrylic emulsion, the amino resin is Zhanxin Cymel 303, the closed water-based catalyst is Nacure 5925, the wetting agent is Yingchuo TEGO WET 872, and the leveling agent is a Yingchuo 420 leveling agent.

Preferably, the preparation process of the water-based steel barrel coating is characterized by comprising the following steps: the method comprises the following steps:

s1: preparing epoxy modified acrylic resin;

s2: preparing epoxy phosphate;

s3, preparing color paste: mixing the epoxy modified acrylic resin prepared in the step S1, ethylene glycol monobutyl ether, a DMEA neutralizer, a defoaming agent, an auxiliary dispersing agent, a pigment dispersing agent, deionized water, titanium dioxide and toner in proportion, putting the mixture into a high-speed dispersion machine, dispersing the mixture for 30 minutes at the rotating speed of 900 plus 1100 r/min, and putting the mixture into a sand mill for grinding for 40 minutes in a cooling state to form red pigment with the particle size of less than 6 micrometers;

s4: proportioning according to the proportion: weighing and proportioning the acrylic emulsion, the color paste, the epoxy phosphate prepared in the step S2, the wetting agent, the thickening agent, the amino resin, the dipropylene glycol methyl ether, the leveling agent, the deionized water and the closed water catalyst according to the proportion in the claim 1;

s5, stirring and mixing: stirring the material proportioned according to the S4 at the rotating speed of 200 and 500 revolutions of a high-speed dispersion machine for more than 30 minutes at room temperature, filtering, detecting and packaging to obtain the water-based steel barrel coating.

Preferably, the preparation process of the self-made epoxy modified acrylic resin in the step S1 is as follows:

s11: preparing a base material: preparing 15-20 parts of ethylene glycol butyl ether, dissolving 35-45 parts of Nantong star 901 solid epoxy resin into an epoxy solution, adding 18-30 parts of acrylic acid monomer, and mixing to obtain a base material for later use;

s12: preparing a monomer mixed solution: mixing 17-30 parts of styrene, 45-65 parts of butyl acrylate, 5-15 parts of methyl methacrylate, 1-5 parts of hydroxypropyl acrylate, 3-5 parts of tert-butyl peroxy-2-ethylhexanoate (TBPO) initiator and 10-20 parts of propylene glycol methyl ether solvent to prepare a mixed solution;

s13: preparing other materials: 0.2-1.0 part of tert-butyl peroxy-2-ethylhexanoate (TBPO) initiator, 0.2-1.0 part of propylene glycol methyl ether solution as complementary initiator, 6-16 parts of n-butanol, 20-40 parts of ethylene glycol butyl ether as diluent, and 2.2-3.6 parts of dimethylethanolamine as neutralizer

S14: stirring and mixing:

s141: heating the base material prepared in the step S11 to 95-100 ℃ under the stirring state;

s142: uniformly dropwise adding the mixed solution prepared in the step S12 into the stirred and heated base material for 3 hours, controlling the temperature to be 95-100 ℃, and preserving heat for 1 hour after dropwise adding;

s143: uniformly dropwise adding the tert-butyl peroxy-2-ethylhexanoate (TBPO) initiator prepared in the step S13 and the propylene glycol methyl ether solution into the material prepared in the step S14.2 for 0.5 hour, and preserving heat for 2.5-3 hours at the temperature of 95-100 ℃ after dropwise adding;

s144: and (4) after heat preservation, cooling to 70 ℃, adding the n-butyl alcohol, the ethylene glycol butyl ether and the dimethyl ethanolamine (DMEA) prepared in the step S13, uniformly stirring, continuously cooling to below 50 ℃, filtering and packaging for later use. The water-soluble epoxy modified acrylic resin is prepared by the above process.

Preferably, the preparation process of the homemade epoxy phosphate in the step S2 is as follows:

s21: preparing an epoxy solution: heating 3.0-5.0 parts of ethylene glycol monobutyl ether and 7-10 parts of Nantong star 850S epoxy resin to 45 ℃ under the stirring state, and dissolving to prepare an epoxy solution;

s22, pre-dissolving: dissolving 0.6-1.2 parts of 85% phosphoric acid, 0.2-1.0 part of deionized water and 0.2-1.0 part of butyl cellosolve at room temperature in advance;

s23, preparing other materials: preparing 2.2-7.0 parts of ethylene glycol butyl ether and 0.6-1.6 parts of dimethylethanolamine; s24: phosphorization:

s241: adding the epoxy solution prepared in the step S22 into the material pre-dissolved in the step S21, heating to 60 ℃, preserving heat for 1 hour, then heating to 100-110 ℃ within 1 hour, and preserving heat for 3 hours;

s242: adding 2.0-5.0 parts of butyl cellosolve and cooling to 50 ℃;

s243: adding 0.6-1.6 parts of dimethylethanolamine and 0.2-2.0 parts of ethylene glycol monobutyl ether and ethylene glycol monobutyl ether, and uniformly stirring to prepare the water-soluble epoxy phosphate resin.

Preferably, the application method of the water-based steel drum coating is used for coating the surface of a steel drum and comprises the following steps: s1: feeding iron: opening the whole sheet package, conveying the sheet package to the front section of the production line by a forklift, placing the sheet package on a pinch roll, and continuously and sequentially conveying the iron plates to a pretreatment working section in a magnetic suction mode;

s2: pretreatment: deoiling and degreasing a metal plate by using special treatment liquid, carrying out spray cleaning, then passivating by using passivation liquid, and heating and drying the metal plate;

s3: and (3) roller coating: the method comprises the following steps of (1) adsorbing a metal plate by magnetic force, placing the metal plate on a conveying chain, placing a water-based paint in a trough in advance, coating the metal plate twice through a rubber roll, and immediately coating the metal plate with the water-based paint for the second time without baking after the first time of coating;

s4: baking: and the coated metal plate enters a tunnel type drying room through a conveying line at the speed of 30-40 sheets/min. Setting the baking temperature of the drying room to be 140 ℃ at the front section, 140 ℃ at the middle section and 170 ℃ at the rear end, and controlling the panel to pass through the rear end constant temperature area for 3-5 minutes;

s5: and (3) cooling: then cooling the plate by air blast;

s6: receiving: the metal sheets are stacked orderly through a material receiving machine;

s7: barrel making: and (5) cutting, rolling, carrying out resistance welding on the sheet in the step S4, coating welding seam paint, sealing the upper cover and the lower cover, and finally manufacturing the packaging barrel.

The technical scheme of the invention has the following beneficial effects:

1. after the water-based steel drum coating in the scheme is formed into a film, the bonding force between the films is good, the surface flatness is high, the defects of bubbles, leveling and the like cannot be generated, the second layer of coating can be directly coated without baking after the coating is coated for the first time, the coating process is reduced, meanwhile, the coating has high wear resistance and boiling resistance after the film is formed, and the surface of a steel drum can be effectively protected from being damaged.

2. According to the scheme, the self-prepared epoxy phosphate enhances the adhesive force of the water-based steel barrel coating, and solves the problems that the adhesive force and the impact resistance of a steel barrel paint film are poor, and the paint film is easy to fall off.

3. According to the scheme, the special dispersing agent is added to promote the pigment and filler to be fully dispersed, the coating is free of fine particles, leveling and auxiliary agent wetting are added, and the surface of the coating is smooth by a comprehensive measure of synthesizing epoxy modified acrylic resin with a proper molecular weight and epoxy phosphate.

4. This scheme utilizes the coating mode coating paint of roller coat with steel drum sheet earlier, carries out the system bucket again, and the spraying gets the mode earlier for traditional system bucket again, has not only avoided the extravagant problem of coating that the spraying leads to, utilizes the characteristics of toasting fast to promote work efficiency simultaneously.

5. According to the scheme, the dimethyl ethanolamine is added, the intersolubility among the raw materials is improved, meanwhile, the addition of the water-based closed catalyst is favorable for improving the reaction efficiency, and the curing rate of the water-based paint can be effectively improved when the water-based paint of the steel drum is coated on the surface of the steel drum, so that the production efficiency of the steel drum is improved.

Detailed Description

The invention discloses a preparation process of a water-based steel barrel coating, which comprises the following steps:

s1: preparing epoxy modified acrylic resin;

specifically, the preparation process of the self-made epoxy modified acrylic resin in the step S1 is as follows:

s11: preparing a base material: preparing 15-20 parts of ethylene glycol butyl ether, dissolving 35-45 parts of Nantong star 901 solid epoxy resin into an epoxy solution, adding 18-30 parts of acrylic acid monomer, and mixing to obtain a base material for later use;

s12: preparing a monomer mixed solution: mixing 17-30 parts of styrene, 45-65 parts of butyl acrylate, 5-15 parts of methyl methacrylate, 1-5 parts of hydroxypropyl acrylate, 3-5 parts of tert-butyl peroxy-2-ethylhexanoate (TBPO) initiator and 10-20 parts of propylene glycol methyl ether solvent to prepare a mixed solution;

s13: preparing other materials: 0.2-1.0 part of tert-butyl peroxy-2-ethylhexanoate (TBPO) initiator, 0.2-1.0 part of propylene glycol methyl ether solution as supplementary initiator, 6-16 parts of n-butanol, 20-40 parts of ethylene glycol butyl ether as diluent and 2.2-3.6 parts of dimethylethanolamine as neutralizer are prepared;

s14: stirring and mixing:

s141: heating the base material prepared in the step S11 to 95-100 ℃ under the stirring state;

s142: uniformly dropwise adding the mixed solution prepared in the step S12 into the stirred and heated base material for 3 hours, controlling the temperature to be 95-100 ℃, and preserving heat for 1 hour after dropwise adding;

s143: uniformly dropwise adding the tert-butyl peroxy-2-ethylhexanoate (TBPO) initiator prepared in the step S13 and the propylene glycol methyl ether solution into the material prepared in the step S14.2 for 0.5 hour, and preserving heat for 2.5-3 hours at the temperature of 95-100 ℃ after dropwise adding;

s144: and (4) after heat preservation, cooling to 70 ℃, adding the n-butyl alcohol, the ethylene glycol butyl ether and the dimethyl ethanolamine (DMEA) prepared in the step S13, uniformly stirring, continuously cooling to below 50 ℃, filtering and packaging for later use. The water-soluble epoxy modified acrylic resin is prepared by the process;

according to the above preparation process, the following examples and comparative examples are provided:

example 1:

the method comprises the following steps:

s11: preparing a base material: preparing 18 parts of ethylene glycol butyl ether, dissolving 42 parts of Nantong star 901 solid epoxy resin into an epoxy solution, adding 25 parts of acrylic acid monomer, and mixing to obtain a base material for later use;

s12: preparing a monomer mixed solution: mixing 24 parts of styrene, 55 parts of butyl acrylate, 10 parts of methyl methacrylate, 3 parts of hydroxypropyl acrylate, 4.2 parts of tert-butyl peroxy-2-ethylhexanoate initiator and 12 parts of propylene glycol methyl ether solvent to prepare a mixed solution;

s13: preparing other materials: 0.4 part of tert-butyl peroxy-2-ethylhexanoate initiator, 0.8 part of propylene glycol methyl ether solution as supplementary initiator, 10 parts of n-butyl alcohol, 32.4 parts of ethylene glycol butyl ether as diluent and 2.6 parts of dimethylethanolamine as neutralizer are prepared;

s14: stirring and mixing:

s141: heating the base material prepared in the step S11 to 95-100 ℃ under the stirring state;

s142: uniformly dropwise adding the mixed solution prepared in the step S12 into the stirred and heated base material within 3 hours, controlling the temperature to be 95-100 ℃, and preserving heat for 1 hour after dropwise adding;

s143: uniformly dropwise adding the tert-butyl peroxy-2-ethylhexanoate initiator prepared in the step S13 and the propylene glycol methyl ether solution into the material prepared in the step S14.2 for 0.5 hour, and preserving heat for 2.5-3 hours at the temperature of 95-100 ℃ after dropwise adding;

s144: and (4) after heat preservation, cooling to 70 ℃, adding the n-butyl alcohol, the ethylene glycol butyl ether and the dimethylethanolamine prepared in the step S13, stirring uniformly, continuously cooling to below 50 ℃, filtering and packaging for later use. The water-soluble epoxy modified acrylic resin H1 is prepared by the above process.

Comparative example 1:

the method comprises the following steps:

s11: preparing a base material: preparing 12 parts of ethylene glycol butyl ether, dissolving 32 parts of Nantong star 850S solid epoxy resin into an epoxy solution, adding 25 parts of acrylic acid monomer, and mixing to obtain a base material for later use;

s12: preparing a monomer mixed solution: mixing 24 parts of styrene, 55 parts of butyl acrylate, 10 parts of methyl methacrylate, 3 parts of hydroxypropyl acrylate, 4.2 parts of tert-butyl peroxy-2-ethylhexanoate initiator and 12 parts of propylene glycol methyl ether solvent to prepare a mixed solution;

s13: preparing other materials: 0.4 part of tert-butyl peroxy-2-ethylhexanoate initiator, 0.8 part of propylene glycol methyl ether solution as supplementary initiator, 10 parts of n-butyl alcohol, 32.4 parts of ethylene glycol butyl ether as diluent and 2.6 parts of dimethylethanolamine as neutralizer are prepared;

s14: stirring and mixing:

s141: heating the base material prepared in the step S11 to 95-100 ℃ under the stirring state;

s142: uniformly dropwise adding the mixed solution prepared in the step S12 into the stirred and heated base material within 3 hours, controlling the temperature to be 95-100 ℃, and preserving heat for 1 hour after dropwise adding;

s143: uniformly dropwise adding the tert-butyl peroxy-2-ethylhexanoate initiator prepared in the step S13 and the propylene glycol methyl ether solution into the material prepared in the step S14.2 for 0.5 hour, and preserving heat for 2.5-3 hours at the temperature of 95-100 ℃ after dropwise adding;

s144: and (4) after heat preservation, cooling to 70 ℃, adding the n-butyl alcohol, the ethylene glycol butyl ether and the dimethylethanolamine prepared in the step S13, stirring uniformly, continuously cooling to below 50 ℃, filtering and packaging for later use. The water-soluble epoxy modified acrylic resin H2 is prepared by the above process.

S2: preparing epoxy phosphate;

specifically, the preparation process of the self-made epoxy phosphate in the step S2 is as follows:

s21: preparing an epoxy solution: heating 3.0-5.0 parts of ethylene glycol monobutyl ether and 7-10 parts of Nantong star 850S epoxy resin to 45 ℃ under the stirring state, and dissolving to prepare an epoxy solution;

s22, pre-dissolving: dissolving 0.6-1.2 parts of 85% phosphoric acid, 0.2-1.0 part of deionized water and 0.2-1.0 part of butyl cellosolve at room temperature in advance;

s23, preparing other materials: preparing 2.2-7.0 parts of ethylene glycol butyl ether and 0.6-1.6 parts of dimethylethanolamine;

s24: phosphorization:

s241: adding the epoxy solution prepared in the step S32 into the material pre-dissolved in the step S31, heating to 60 ℃, preserving heat for 1 hour, then heating to 100-110 ℃ within 1 hour, and preserving heat for 3 hours;

s242: adding 2.0-5.0 parts of butyl cellosolve and cooling to 50 ℃;

s243: adding 0.6-1.6 parts of dimethylethanolamine and 0.2-2.0 parts of ethylene glycol monobutyl ether and ethylene glycol monobutyl ether, and uniformly stirring to prepare the water-soluble epoxy phosphate resin.

According to the above preparation process, the following examples and comparative examples are provided:

example 2:

s21: preparing an epoxy solution: heating 4.6 parts of ethylene glycol monobutyl ether and 8.6 parts of Nantong star 850S epoxy resin to 45 ℃ under a stirring state, and dissolving to prepare an epoxy solution;

s22: pre-dissolving: dissolving 0.87 part of 85% phosphoric acid, 0.4 part of deionized water and 0.8 part of butyl cellosolve at room temperature in advance;

s23: preparing other materials: preparing 3.7 parts of ethylene glycol butyl ether and 1 part of dimethylethanolamine;

s24: phosphorization:

s241: adding the epoxy solution prepared in the step S22 into the material pre-dissolved in the step S21, heating to 60 ℃, preserving heat for 1 hour, then heating to 100-110 ℃ within 1 hour, and preserving heat for 3 hours;

s242: adding 3.3 parts of ethylene glycol butyl ether and then cooling to 50 ℃;

s243: adding 1 part of dimethylethanolamine and 0.4 part of ethylene glycol monobutyl ether, and uniformly stirring to prepare the water-soluble epoxy phosphate resin L1.

Comparative example 2:

s21: preparing an epoxy solution: heating 8.69 parts of ethylene glycol butyl ether and 9.66 parts of Korean Kokoku SC-214 solid epoxy resin to 80 ℃ under a stirring state, and dissolving to prepare an epoxy solution;

s22: pre-dissolving: dissolving 0.32 part of 85% phosphoric acid, 0.18 part of deionized water and 0.15 part of butyl cellosolve at room temperature in advance;

s23: preparing other materials: 0.55 parts of ethylene glycol butyl ether and 0.21 part of dimethylethanolamine are prepared;

s24: phosphorization:

s241: adding the material pre-dissolved in the step S22 into the epoxy solution prepared in the step S21, heating to 90 ℃, preserving heat for 1 hour, then heating to 110-115 ℃ within 1 hour, and preserving heat for 3 hours;

s242: adding 0.15 part of ethylene glycol butyl ether and then cooling to 50 ℃;

s243: adding 0.21 part of dimethylethanolamine and 0.4 part of ethylene glycol monobutyl ether, and uniformly stirring to prepare the water-soluble epoxy phosphate resin L2.

S3, preparing color paste: mixing the epoxy modified acrylic resin prepared in the step S1, ethylene glycol monobutyl ether, dimethyl ethanolamine neutralizer, antifoaming agent, auxiliary dispersant, pigment dispersant, deionized water, titanium dioxide and toner in proportion, putting the mixture into a high-speed dispersion machine, dispersing the mixture for 30 minutes at the rotating speed of 900 plus 1100 rpm, and putting the mixture into a sand mill for grinding for 40 minutes in a cooling state to form red pigment with the particle size of less than 6 micrometers;

according to the above preparation process, the following examples and comparative examples are provided:

example 3:

14.05 parts of epoxy modified acrylic resin H1 prepared in example 1, 7.81 parts of ethylene glycol butyl ether, 0.13 part of dimethylethanolamine neutralizer, 0.39 part of Yingchuang 104 wetting agent, 0.31 part of Yingchuang AD01 defoamer, 1.5 parts of TEGO dispers 760W auxiliary dispersant, 4.5 parts of zetasperse3800 pigment dispersant, 25.76 parts of deionized water, 17.18 parts of Hensmei TR092, 29.67 parts of Kelaien titanium F3RK red pigment and 0.09 part of 5000 water-based carbon black slurry (Shanghai Baiyan) are mixed, put into a high-speed dispersion machine and dispersed for 30 minutes at the rotating speed of 900-;

comparative example 3:

equal amount of TEGO dispers 755W pigment dispersant is substituted for zetasperse3800 pigment dispersant, and the preparation and preparation process of the rest materials are the same as those in example 3, so that red pigment X2 with the particle size of less than 6 microns is prepared; comparative example 4:

the epoxy modified acrylic resin H2 prepared in comparative example 1 is equally used to replace the epoxy modified acrylic resin H1 prepared in example 1, and the preparation and preparation process of the rest materials are the same as those in example 3, so that red pigment X3 with the particle size of less than 6 microns is prepared;

comparative example 5:

replacing the epoxy modified acrylic resin H1 prepared in example 1 with the Taixing Jiaxiang 810W water-based acrylic resin in equal amount, and preparing red pigment X4 with the particle size of less than 6 microns by the same preparation and preparation process as in example 3 with the rest materials;

comparative example 6:

the epoxy modified acrylic resin H1 prepared in example 1 is replaced by deionized water in equal amount, and the preparation and preparation process of other materials are the same as those in example 3, so that red pigment X5 with the particle size of less than 6 microns is prepared;

the test results for color pastes X1-X5 made according to example 3 and comparative examples 3-6 are as follows:

as can be seen from the comparison of the color paste states of X1 and X3 and X4 in the above table, the color paste in the present embodiment can prevent the problems of delamination and agglomeration compared with the epoxy modified acrylic resin prepared in comparative example 1 and the acrylic resin commonly used in the market by adding the epoxy modified acrylic resin prepared in example 1, and at the same time, the addition of the epoxy modified acrylic resin can be seen to have a greater influence on the color paste state compared with the X5 prepared in comparative example 6 by comparing the X1 prepared in example 3 with the X5 prepared in comparative example 6.

S4: proportioning according to the proportion: at least comprises the following components in parts by weight:

s5, stirring and mixing: stirring the material proportioned according to the S4 at the rotating speed of 200 and 500 revolutions of a high-speed dispersion machine for more than 30 minutes at room temperature, filtering, detecting, and packaging to obtain the water-based steel barrel coating.

According to the proportioning and preparation process of different materials, the following examples and comparative examples are provided:

example 4:

s4, proportioning according to the proportion: at least comprises the following components in parts by weight:

specifically, the acrylic emulsion is Wanhuaantkote 2083 acrylic emulsion, the epoxy modified acrylic resin is the epoxy modified acrylic resin H1 prepared according to example 1, the color paste is the color paste X1 prepared according to example 3, the self-made epoxy phosphate is the epoxy phosphate L1 prepared according to example 2, the wetting agent is winning TEGO WET 872, the thickening agent is Wanhua U608 thickening agent, the amino resin is Zhanxin cymel 303 amino resin, the leveling agent is winning leveling agent 420, and the closed water-based catalyst is Jinzhou nacure 5925 catalyst.

S5: stirring and mixing: stirring the material proportioned according to the S4 at the rotating speed of 200 and 500 revolutions of a high-speed dispersion machine for more than 30 minutes at room temperature, filtering, detecting and packaging to obtain the water-based steel barrel coating T1.

Example 5:

s4, proportioning according to the proportion: at least comprises the following components in parts by weight:

specifically, the acrylic emulsion is Wanhuaantkote 2083 acrylic emulsion, the color paste is color paste X1 prepared in example 3, the self-made epoxy phosphate is epoxy phosphate L1 prepared in example 2, the wetting agent is Yingchuo TEGO WET 872, the thickening agent is a Bikk 420 thickening agent, the amino resin is Zhanxin cymel 303 amino resin, the leveling agent is Yingchuo 420 leveling agent, and the closed water-based catalyst is a Jinshi Nacure 5925 catalyst.

S5: stirring and mixing: stirring the material proportioned according to the S4 at the rotating speed of 200 and 500 revolutions of a high-speed dispersion machine for more than 30 minutes at room temperature, filtering, detecting and packaging to obtain the water-based steel barrel coating T2.

Example 6:

s4, proportioning according to the proportion: at least comprises the following components in parts by weight:

specifically, the acrylic emulsion is Wanhuaantkote 2083 acrylic emulsion, the color paste is color paste X1 prepared in example 3, the self-made epoxy phosphate is epoxy phosphate L1 prepared in example 2, the wetting agent is Yingchuo TEGO WET 872, the amino resin is Zhanxin cymel 327 amino resin, the leveling agent is Yingchuo 420 leveling agent, and the closed water-based catalyst is Jinshi nacure 5925 catalyst. S5: stirring and mixing: stirring the material proportioned according to the S4 at the rotating speed of 200 and 500 revolutions of a high-speed dispersion machine for more than 30 minutes at room temperature, filtering, detecting and packaging to obtain the water-based steel barrel coating T3.

Comparative example 6:

using comparative example 2 instead of the epoxy phosphate of example 2, the same procedure as in example 4 was conducted to obtain water-based steel drum paint T4.

Comparative example 7:

using comparative example 2 in place of the epoxy phosphate of example 2, the same procedure as in example 5 was conducted to obtain an aqueous steel drum dope T5.

Comparative example 8:

the humectant was a winning TEGO WET 245 instead of a winning TEGO WET 872, and the cosolvent was ethylene glycol butyl ether instead of dipropylene glycol methyl ether, the same as in example 5, to make a waterborne steel drum coating T6.

Comparative example 9:

an aqueous steel drum paint T7 was prepared by using 0.05 part of Cikinawa 2500 closed aqueous catalyst in place of Cikinawa 5925 catalyst and 5.75 parts of Zhan new cymel 1156 amino resin in place of Zhan new cymel 303, with the same ingredients as in Process example 5.

The test results for an aqueous steel drum coating made according to examples 4-6 and comparative examples 6-9, T1-T7, are as follows:

according to the comparison between T1-T3 and T4-T5 in the table, the self-made epoxy phosphate is added in the scheme, so that the bonding force of the coating can be effectively improved, the surface flatness is improved, and meanwhile, the self-made epoxy phosphate can improve the curing capacity and the adhesive force of the coating on the surface of the steel barrel and prevent the coating from falling off and fading; also, as can be seen from the comparison of T2 with T6, the choice of wetting agent and co-solvent also affects the smoothness of the coating surface.

An application method of water-based steel drum paint for coating the surface of a steel drum comprises the following steps:

s1: feeding iron: opening the whole sheet package, conveying the sheet package to the front section of the production line by a forklift, placing the sheet package on a pinch roll, and continuously and sequentially conveying the iron plates to a pretreatment working section in a magnetic suction mode;

s2: pretreatment: deoiling and degreasing a metal plate by using special treatment liquid, carrying out spray cleaning, then passivating by using passivation liquid, and heating and drying the metal plate;

s3: and (3) roller coating: the method comprises the following steps of (1) adsorbing a metal plate by magnetic force, placing the metal plate on a conveying chain, placing a water-based paint in a trough in advance, coating the metal plate twice through a rubber roll, and immediately coating the metal plate with the water-based paint for the second time without baking after the first time of coating;

s4: baking: and the coated metal plate enters a tunnel type drying room through a conveying line at the speed of 30-40 sheets/min. Setting the baking temperature of the drying room to be 140 ℃ at the front section, 140 ℃ at the middle section and 170 ℃ at the rear end, and controlling the panel to pass through the rear end constant temperature area for 3-5 minutes;

s5: and (3) cooling: then cooling the plate by air blast;

s6: receiving: the metal sheets are stacked orderly through a material receiving machine;

s7: barrel making: and (5) cutting, rolling, carrying out resistance welding on the sheet in the step S4, coating welding seam paint, sealing the upper cover and the lower cover, and finally manufacturing the packaging barrel.

The coating method adopts the steps of coating firstly and then making the barrel, so that the coating is saved compared with the mode of making the barrel firstly and then spraying, and meanwhile, the coating mode can ensure that the coating on the surface of the steel barrel is smoother, and uneven coating is avoided.

The invention has various embodiments, and all technical solutions formed by adopting equivalent transformation or equivalent transformation are within the protection scope of the invention.