CN114149708A

CN114149708A - Two-component waterborne polyurethane antibacterial and mildewproof coating for mildew prevention of cigarette factories and preparation method thereof

Info

Publication number: CN114149708A
Application number: CN202111561758.9A
Authority: CN
Inventors: 全毅; 郭建光; 王涛; 李航; 付涛; 董俊; 牛好强; 刘许民
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-12-20
Filing date: 2021-12-20
Publication date: 2022-03-08
Anticipated expiration: 2041-12-20
Also published as: CN114149708B

Abstract

The invention provides a two-component waterborne polyurethane antibacterial and mildewproof coating for mildew resistance in a cigarette factory, which comprises a component A and a component B which are mixed, wherein the component A comprises the following components: deionized water, water-based modified acrylic resin, a first wetting agent, a defoaming agent, water-based zinc pyrithione, water-based 2-n-octyl-4-isothiazoline-3-ketone, 3-iodo-2-propynyl butyl carbamate, a second wetting agent, water-based white slurry, matting powder, kaolin, a flatting agent and a thickening agent; the component B is a curing agent, and when the coating is used, the component A and the component B are mixed and then uniformly coated on a wall surface. The invention has the beneficial effects that: the invention can effectively inhibit the propagation of the mildew in the smoke factory on the wall surface, and the formed coating has excellent aging resistance, ensures no color change after long-term use, does not influence the beauty, and simultaneously has lower manufacturing cost and simple and convenient construction, thereby creating convenient conditions for large-scale popularization.

Description

Two-component waterborne polyurethane antibacterial and mildewproof coating for mildew prevention of cigarette factories and preparation method thereof

Technical Field

The invention relates to the field of mildew prevention of wall surfaces of cigarette factories, in particular to a two-component waterborne polyurethane antibacterial mildew-proof coating for the mildew prevention of the cigarette factories and a preparation method thereof.

Background

The mould strains causing the wall surface to mildew in different environments are different, so that the research on the special mildew-proof wall surface coating in the special environment is very important.

Cigarette production factories in China, particularly walls and top surfaces of rooms such as a tobacco shred manufacturing workshop and a tobacco shred storage room are in high-temperature and high-humidity environments for a long time, so that good conditions are provided for breeding of various moulds, and moreover, tobacco powder deposited on the walls and the top surfaces also provides rich nutrients for growth of special moulds, so that a large amount of mould phenomena occur on the walls and the top surfaces of a plurality of tobacco factories in China, the attractiveness of the production workshops is influenced, more importantly, the production of the moulds also seriously influences the sanitary quality of cigarettes, and the serious adverse effects are also caused on the physical and mental health of workers working in the mould environment for a long time.

The existing smoke factory uses mildew-proof paint for basement or food factory, the paint mainly uses acrylic acid as main film forming substance, the smoke factory uses the paint to carry out coating treatment, and practice proves that the mildew-proof effect is not good.

Some smoke plants try to use ceramic tiles to decorate wall surfaces to prevent mildew, but because the ceramic tiles are stuck too high, the ceramic tiles fall off, the ceramic tiles cannot completely cover the wall surfaces and the wall tops, and the splicing gaps of the ceramic tiles still can generate mildew, or the expected mildew-proof effect cannot be achieved.

Some smoke plants adopt the aluminous gusset plate to carry out the wall fitment in addition, and the fossil fragments need be erect in the aluminous gusset plate installation, though not long mould of aluminous gusset plate self, nevertheless still can influence cigarette quality and personnel health at the wall of aluminous gusset plate back fossil fragments one side long mould to it is inconvenient that maintenance after high and the operation of aluminous gusset plate cost.

Therefore, the problem of mildew generation in the cigarette factory cannot be solved by the existing coating and method for preventing the wall surface of the cigarette factory from mildew, and a method suitable for preventing the wall surface of the cigarette factory from mildew is urgently needed.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide the two-component waterborne polyurethane antibacterial and mildewproof coating for the mildewproof of the cigarette factory, and the invention also aims to provide a preparation method and a use method of the two-component waterborne polyurethane antibacterial and mildewproof coating for the mildewproof of the cigarette factory.

The purpose of the invention is realized by the following technical scheme.

A two-component waterborne polyurethane antibacterial mildew-proof coating for preventing mildew in a cigarette factory comprises a component A and a component B which are mixed, wherein,

the component A comprises water-based modified acrylic resin, water-based zinc pyrithione, water-based 2-n-octyl-4-isothiazoline-3-ketone, butyl carbamate-3-iodine-2-propynyl ester, water-based white slurry and coating auxiliary materials;

the component B is a curing agent.

Preferably, the water-based zinc pyrithione is added in an amount of not less than 2.5% by weight, the water-based 2-n-octyl-4-isothiazolin-3-one is added in an amount of not less than 3.4% by weight, and the burbamate-3-iodo-2-propynyl ester is added in an amount of not less than 2.7% by weight, based on the total weight of the component A.

Preferably, the water-based zinc pyrithione is added in an amount of not less than 3% by weight, the water-based 2-n-octyl-4-isothiazolin-3-one is added in an amount of not less than 3.5% by weight, and the burbamate-3-iodo-2-propynyl ester is added in an amount of not less than 3% by weight, based on the total weight of the component a.

Preferably, the amount of the water-based zinc pyrithione added to the component A is 3% by weight, the amount of the water-based 2-n-octyl-4-isothiazolin-3-one added to the component A is 3.5% by weight, and the amount of the 3-iodo-2-propynyl butylcarbamate added to the component A is 3% by weight.

Preferably, the addition amount of the waterborne modified acrylic resin is 50% of the total weight of the component A.

In any of the above embodiments, preferably, the aqueous modified acrylic resin is an aqueous hydroxy-functional polyacrylic acid.

Preferably, in any of the above embodiments, the amount of the aqueous white slurry added is 20% of the total weight of the component A.

Preferably, in any of the above schemes, the aqueous white slurry comprises the following components in percentage by weight:

preferably, in any of the above embodiments, the pigment is rutile titanium dioxide.

Preferably, in any one of the above schemes, the coating auxiliary materials include a first wetting agent, a defoaming agent, a second wetting agent, matting powder, kaolin, a leveling agent, a thickening agent and deionized water.

Preferably, in any one of the above schemes, the addition amount of each component of the coating auxiliary material is as follows according to the total weight of the component A:

preferably, in any of the above embodiments, the first humectant is humectant 140, and the second humectant is propylene glycol.

Preferably, in any of the above embodiments, the curing agent is a hydrophilic aliphatic polyisocyanate such as Hexamethylene Diisocyanate (HDI).

A preparation method of a component A in a two-component waterborne polyurethane antibacterial and mildewproof coating for mildew prevention in a cigarette factory comprises the following specific steps:

step one, adding deionized water and water-based modified acrylic resin, and dispersing for 5min at the speed of 600 r/min;

adding a first wetting agent, a defoaming agent, water-based zinc pyrithione, water-based 2-n-octyl-4-isothiazoline-3-ketone and 3-iodo-2-propynyl butylcarbamate, and dispersing at the speed of 1200r/min for 30 min;

adding aqueous white slurry, matting powder and kaolin, and dispersing at the speed of 1200r/min for 30 min;

step four, adding a flatting agent and a thickening agent, and dispersing for 15min at the speed of 600 r/min;

and step five, detecting, filtering and packaging.

Preferably, the method for preparing the aqueous white slurry in the third step comprises the following steps:

step one, adding deionized water, a neutralizing agent and an antiseptic bactericide, and dispersing for 10min at the speed of 1200 r/min;

secondly, adding a thickening thixotropic agent, and dispersing for 30min at the speed of 1200 r/min;

thirdly, adding a dispersing agent, a flatting agent, a defoaming agent and a dispersing agent, and dispersing at the speed of 1200r/min for 30 min;

fourthly, adding pigment, and dispersing for 30min at the speed of 1200r/min to obtain a qualified product with the fineness of not more than 30 microns.

A use method of a two-component waterborne polyurethane antibacterial mildew-proof coating for mildew prevention in a cigarette factory comprises the following steps:

s1, uniformly stirring the component A and the component B to obtain the coating;

and S2, uniformly coating the coating obtained in the step S1 twice, and superposing and continuously and uniformly coating the coating for the second time after the first time is dried.

Drawings

FIG. 1 is a graph of mildew resistance data after the mildew preventive A1 is adopted;

FIG. 2 is a graph of mildew resistance data after the mildew preventive aid A2 is adopted;

FIG. 3 is a graph of mildew resistance data after the mildew preventive A3 is adopted;

FIG. 4 is a graph of the mildew resistance data after the use of test 1, test 2, test 3 and test 4.

The invention has the beneficial effects that:

the coating is a water-based environment-friendly coating, so that the quality of tobacco products is not influenced, the coating and a concrete substrate can be bonded excellently, the coating is prevented from falling off after long-term use, a coating formed by the coating has excellent water resistance, the coating is prevented from peeling and powdering after long-term use in a high-humidity environment, and the coating also has excellent nicotine resistance, and is prevented from being corroded and polluted after long-term use in a nicotine environment.

The coating formed after the coating is coated has a smooth and compact surface, so that tobacco dust is not easy to deposit (the tobacco dust can provide nutrients for moulds), and thus mould breeding is reduced.

The coating formed by the coating has excellent aging resistance, ensures no color change after long-term use, keeps beautiful appearance, has lower manufacturing cost and simple and convenient construction, and creates convenient conditions for large-scale popularization and use.

Detailed Description

The technical solution of the present invention is further illustrated by the following specific examples.

Through the detection of the microbial detection center of the research institute of food fermentation industry in China, the dominant strains in the mold in the tobacco plant are shown in Table 1:

TABLE 1 predominant species in mold in tobacco plants

Serial number	Dominant bacterial species
		1	Periopsis latticis Byssochlamysspeciis
2	Aspergillus tamarii
		3	Aspergillus herculus ochraceus
4	Penicillium chrysogenum
		5	Aspergillus versicolor 1Aspergillus versicolor
6	Aspergillus versicolor 2Aspergillus versicolor
		7	Penicillium citrinum

Based on the strains, the mildew-proof wall paint for the tobacco factories is designed.

Determination of basic film-forming material of mildew-proof wall paint in smoke factory

According to the design of a food-grade factory, the mildew-proof wall paint of a cigarette factory firstly considers the water-based environment-friendly paint, and common water-based resins comprise water-based acrylic resin, water-based epoxy resin, water-based polyurethane resin, water-based fluorocarbon resin and the like. The film-forming material of the water-based mildew-proof coating which is usually used for basements, tunnels and various food factories mostly adopts water-based acrylic resin in consideration of material cost, and preferably adopts water-based epoxy resin. Although the environment-friendly performance of the resin is qualified, other performances of the resin have more defects for producing the coating for preventing mildew on the wall surface of a cigarette factory. Because the recoating performance of the aqueous fluorocarbon resin is poor, the aqueous polyurethane resin is selected as a basic film forming substance of the mildew-proof wall coating in a smoke factory.

Thus, the performance and denseness of the aqueous acrylic resin, the aqueous epoxy resin and the aqueous urethane resin were tested.

1.1 comparative testing of resin Properties

Comparative resin properties test data are shown in table 2:

TABLE 2 comparative testing of resin Properties

As can be seen from Table 2: the bonding strength, the water resistance, the nicotine resistance and the aging resistance of the coating which takes the waterborne polyurethane as the basic film forming substance and the base material are far better than those of waterborne acrylic acid and waterborne epoxy coatings.

1.2 coating Density test

The results of the coating densification test are shown in table 3:

table 3 coating denseness test

The stain resistance value is detected from 1 to 5 according to the standard JC/T908-2013, the smaller the value is, the more excellent the stain resistance performance is, and the stain resistance index is the sum of the stain resistance values of all reagent tests. The test data shows that: the aqueous epoxy is poor in organic acid resistance, and the aqueous acrylic acid is not resistant to solution penetration.

Stain resistance index as shown in table 3: waterborne polyurethane < waterborne epoxy < waterborne acrylic, therefore, stain resistance: waterborne polyurethane > waterborne epoxy > waterborne acrylic.

The conclusion of this test is: from the sum of the stain resistance values, it is clear that the stain resistance of the waterborne polyurethane coating is better than that of the waterborne acrylic and waterborne epoxy coatings.

Based on the tests, the water-based polyurethane can be used as the basic substance of the mildewproof wall coating of the cigarette factory to obtain a more compact and stain-resistant coating, and has excellent adhesive property, water resistance, nicotine resistance and aging resistance. Provides powerful guarantee for the long-acting mildew resistance of the mildew-proof wall coating of the smoke factory.

Secondly, screening varieties and contents of mildew-proof auxiliary agents of tobacco factories

2.1 testing of the mildewproof auxiliary A1 on the basis of different addition amounts for 30 days

The components of the component A after the mildew-proof auxiliary A1 is added are shown in the table 4:

TABLE 4 ingredient Table of ingredient A containing the mildewproofing auxiliary A1

The ingredients of component B are as in table 5:

TABLE 5 ingredient Table for ingredient B

As shown in fig. 1, the experimental data show that: when the addition amount of the mildew-proof auxiliary A1 is less than 2.5%, the mildew is seriously bred, and the mildew-proof performance does not have a remarkable effect; after the mildew resistance is more than 2.5 percent, the mildew area tends to be stable and almost unchanged, and the mildew resistance reaches saturation. From this set of experiments we conclude that: when the addition amount of the mildew-proof auxiliary A1 is 2.5%, the mildew-proof effect is optimal, and the accurate data shows that the mildew-proof killing effect can reach 92%.

When the addition amount of the mildew-proof auxiliary A1 is 2.5%, 8% of the mildew is not killed. Through the detection and identification of the microorganism detection center of the research institute of food fermentation industry in China, 6 dominant molds (including rhizopus pinosus, aspergillus flavus, aspergillus herpotus, penicillium acremonium, aspergillus versicolor 1 and aspergillus versicolor 2) in main strains in a tobacco plant are killed, and one of penicillium citrinum and other molds (non-dominant molds) are not killed. The single A1 mildew-proof auxiliary agent cannot completely kill the mildew.

2.2 testing the mildew-proof auxiliary A2 on the basis of different addition amounts for 30 days

The compositions of the component A after the mildew-proof auxiliary A2 is added are shown in the table 6:

TABLE 6 ingredient Table of ingredient A containing the mildewproofing auxiliary A2

The composition of component B is as in table 7:

TABLE 7 ingredient Table of component B

When the addition amount of the mildew-proof auxiliary A2 is less than 3.4%, the mildew is seriously bred, and the mildew-proof performance does not have a remarkable effect; after the mildew resistance is more than 3.5 percent, the mildew area tends to be stable and almost unchanged, and the mildew resistance reaches saturation. From this set of experiments we conclude that: when the addition amount of the mildew-proof auxiliary A2 is 3.5%, the mildew-proof effect is optimal, and the accurate data shows that the mildew-proof killing effect can reach 58%.

When the addition amount of the mildew-proof auxiliary A2 is 3.5%, 42% of the mildew is not killed. Through the detection and identification of the microorganism detection center of the research institute of food fermentation industry in China, penicillium citrinum and aspergillus versicolor 2 mainly existing in a tobacco plant are killed, and 58% of fungi which are not killed are rhizopus pini, aspergillus flavus, aspergillus hercules, penicillium apiculatum, aspergillus versicolor 1 and other fungi (non-dominant fungi). The single A2 mildew-proof auxiliary agent cannot completely kill the mildew.

2.3 testing the mildew-proof auxiliary A3 on the basis of different addition amounts for 30 days

The compositions of the component A after the mildew-proof auxiliary A3 is added are shown in the table 8:

TABLE 8 ingredient Table of ingredient A containing the mildewproofing auxiliary A3

The ingredients of component B are as in table 9:

TABLE 9 ingredient Table of component B

As shown in fig. 3, when the addition amount of the mildew-proof auxiliary a3 is less than 2.7%, the growth of mold is serious, and the mildew-proof performance does not have a significant effect; after the mildew resistance is more than 3 percent, the mildew area tends to be stable and almost unchanged, and the mildew resistance reaches saturation. From this set of experiments we conclude that: when the addition amount of the mildew-proof auxiliary A3 is 3%, the mildew-proof effect is optimal, and the sterilization effect can reach 20% as shown by accurate data.

When the addition amount of the mildew-proof auxiliary A3 is 3%, 80% of the mildew is not killed. Through the detection and identification of the microorganism detection center of the institute of food fermentation industry in China, aspergillus versicolor 1 and other molds (non-dominant molds) mainly existing in a tobacco plant are killed, and 80% of the molds which are not killed are rhizopus pinus, aspergillus flavus, aspergillus herculensis, penicillium apiculatum, penicillium citrinum and aspergillus versicolor 2. The single A3 mildew-proof auxiliary agent cannot completely kill the mildew.

And (4) conclusion:

1) when the addition amount of the mildew-proof auxiliary A1 is 2.5%, the mildew-proof auxiliary A has a killing effect on 6 dominant molds (including rhizopus pinosus, aspergillus flavus, aspergillus hertzicus, penicillium acremonium, aspergillus versicolor 1 and aspergillus versicolor 2) in main strains of a tobacco plant, and does not have an effect on penicillium citrinum and other molds (non-dominant molds).

2) When the addition amount of the mildew-proof auxiliary A2 is 3.5%, the mildew-proof auxiliary A has a killing effect on 2 dominant molds (penicillium citrinum and aspergillus versicolor 2) in main strains of a tobacco plant, and does not have effects on rhizopus pinosus, aspergillus flavus, aspergillus herculosus, penicillium apiculatum, aspergillus versicolor 1 and other molds (non-dominant molds).

Research on combined action of three mildew-proof auxiliary agents A1, A2 and A3

The addition amounts of the mildew-proofing aids A1, A2 and A3 were divided into 4 test groups, namely:

test 1 group (2.5% of a1 mould inhibitor, 3.5% of a2 mould inhibitor, 3% of A3 mould inhibitor);

test 2 group (3% of a1 mould inhibitor, 3.5% of a2 mould inhibitor, 3% of A3 mould inhibitor);

test 3 group (2.5% of a1 mould inhibitor, 4% of a2 mould inhibitor, 3% of A3 mould inhibitor);

test 4 group (2.5% of A1 mildew preventive, 3.5% of A2 mildew preventive, 3.5% of A3 mildew preventive);

the composition of each test group, component a, is shown in table 10:

watch 10

In this test, the composition of component B is shown in Table 11:

TABLE 11 ingredient Table of ingredient B

The results of test 1, test 2, test 3, and test 4 are shown in table 12:

TABLE 12 test results of test 1, test 2, test 3, and test 4

	Test 1	Test 2	Test 3	Test 4
					Area ratio of mold growth	6％	0％	3％	5％
Rate of killing	94％	100％	97％	95％

And (4) test conclusion:

the test 2 group (3% of A1 mildew preventive, 3.5% of A2 mildew preventive and 3% of A3 mildew preventive) can achieve the effect of not growing mildew for 30 days.

The mildew-proof effect of the test 1 group (2.5% of a1 mildew-proof auxiliary agent, 3.5% of a2 mildew-proof auxiliary agent, 3% of A3 mildew-proof auxiliary agent), the test 3 group (2.5% of a1 mildew-proof auxiliary agent, 4% of a2 mildew-proof auxiliary agent, 3% of A3 mildew-proof auxiliary agent), and the test 4 group (2.5% of a1 mildew-proof auxiliary agent, 3.5% of a2 mildew-proof auxiliary agent, 3.5% of A3 mildew-proof auxiliary agent) were also more effective than the single mildew-proof auxiliary agent, but the different proportions were not as good as the mildew-proof effect of the test 2 group (3% of a1 mildew-proof auxiliary agent, 3.5% of a2 mildew-proof auxiliary agent, 3% of A3 mildew-proof auxiliary agent).

To summarize: for the mold appearing in the tobacco plant, three mildew-proof auxiliary agents A1, A2 and A3 are selected, and the test results show that:

1) the A1 mildew-proof auxiliary agent mainly plays a role in killing dominant mycete (rhizopus pinus, aspergillus flavus, aspergillus hercules, penicillium apiculatum, aspergillus versicolor 1 and aspergillus versicolor 2) in a tobacco plant, and the killing rate can reach 92%;

2) a2 mildew-proof auxiliary agent mainly plays a role in killing penicillium citrinum and aspergillus versicolor 2;

3) the A3 mildew-proof auxiliary agent mainly kills aspergillus versicolor 1 and other moulds (non-dominant moulds);

4) the mildew-proof additive A1 in 3%, the mildew-proof additive A2 in 3% and the mildew-proof additive A3 in 3% can achieve the effect of preventing mildew from growing in 30 days. The three mildew-proof auxiliary agents are applied in a compounding way, and the mildew is prevented jointly, so that the mildew-proof effect is achieved.

Four, two-component waterborne polyurethane antibacterial and mildewproof coating for mildew prevention in cigarette factories, and preparation and use methods thereof

1.1 coating formulation

The formula of the two-component waterborne polyurethane antibacterial and mildewproof coating for the mildewproof of the cigarette factory comprises a component A and a component B which are mixed, wherein the components of the component A are shown in table 13, the components of the component B are shown in table 14, and the components of the waterborne white pulp in the component A are shown in table 15.

TABLE 13 ingredient Table of component A

TABLE 14 ingredient Table of component B

TABLE 15 ingredient Table of aqueous white slurry

Serial number	Name of raw material	Composition of	Content (wt.)
				1	Deionized water	Water (W)	30％
2	Neutralizing agent	N, N-dimethylethanolamine	1％
				3	Antiseptic bactericide	Isothiazolinone		1％
4	Thickening thixotropic agent	Hydroxyethyl cellulose	0.5％
				5	Dispersing agent	Modified polyether	3％
6	Leveling agent	Polyether modified polydimethylsiloxane	1％
				7	Defoaming agent	Polyether siloxane copolymers	1.5％
8	Dispersing agent	Hydrophobically modified ammonium salts of polyacrylic acids	2％
				9	Pigment (I)	Rutile type titanium dioxide	60％

1.2 preparation method of the coating

A process for preparing component a comprising the steps of:

and step five, detecting, filtering and packaging.

Wherein, the preparation method of the aqueous white slurry in the third step comprises the following steps:

1.3 application method and construction process

1.3.1 Material agitation

The topcoat component A was stirred uniformly, then the component B was poured in, stirred uniformly with an electric stirrer for 3 minutes, then poured into another container, and stirred for 2 minutes.

1.3.2 construction

The surface layer is constructed by adopting a roller, the roller coating is carried out twice, the coating interval of each time is 24-48 hours, and the construction of the second time can be carried out after the first time of drying. In addition, the construction of the surface layer should be completed to seal the site and make personnel control. The surface layer constructor should wear the dust-free clothing to carry out uniform coating to form the final surface. In the surface coating process, a roller is used to uniformly coat the surface to form a continuous and uniform coating film. During construction, the coating thickness is noticed, and the coating cannot flow or leak.

Example 1

1.1 determination of mildew-proof effect of composite mildew-proof auxiliary agent on dominant strains in tobacco factories

The test result of the antibacterial material test center of the research institute of physical and chemical technology of Chinese academy of sciences shows that the coating does not mildew in the environment of the dominant bacteria in the tobacco plant, as shown in Table 16.

TABLE 16 test results

1.2 determination of Long-lasting mildew resistance

The long-lasting mildew-resistant effect of the mildew-resistant coating was tested in the THOR laboratory as shown in table 17:

TABLE 17 THOR laboratory Long-term mildew data

Analysis of the data as in table 17 yields: the method is equivalent to the method that the mildew does not grow for more than 5 years in the practical application of the engineering.

1.3 actual tobacco plant usage test

The test results are shown in table 18:

TABLE 18 mildew-proof test for cigarette factory

According to the table 18, at present, in the project of cigarette factories, there are actual cases that the mould does not grow for 9 years, the mould-proof problem is thoroughly solved for the cigarette factories, and the product has long-term mould-proof performance.

While one embodiment of the present invention has been described in detail, the description is only a preferred embodiment of the present invention and should not be taken as limiting the scope of the invention. All equivalent changes and modifications made within the scope of the present invention shall fall within the scope of the present invention.

Claims

1. A two-component waterborne polyurethane antibacterial mildew-proof coating for mildew prevention in a cigarette factory is characterized by comprising the following components in parts by weight: comprises a component A and a component B which are used in a mixing way, wherein,

the component A comprises an aqueous modified acrylic resin, aqueous zinc pyrithione, aqueous 2-n-octyl-4-isothiazoline-3-ketone, butyl carbamate-3-iodo-2-propynyl ester, aqueous white slurry and coating auxiliary materials, wherein the addition amount of the aqueous zinc pyrithione is not less than 2.5 percent of the total weight of the component A, the addition amount of the aqueous 2-n-octyl-4-isothiazoline-3-ketone is not less than 3.4 percent of the total weight of the component A, and the addition amount of the butyl carbamate-3-iodo-2-propynyl ester is not less than 2.7 percent of the total weight of the component A;

the component B is a curing agent.

2. The two-component waterborne polyurethane antibacterial and mildewproof coating for preventing mildew in a cigarette factory, according to claim 1, is characterized in that: the addition amount of the water-based zinc pyrithione in the component A is not less than 3 percent of the total weight of the component A, the addition amount of the water-based 2-n-octyl-4-isothiazolin-3-ketone is not less than 3.5 percent of the total weight of the component A, and the addition amount of the 3-iodo-2-propynyl butyl carbamate is not less than 3 percent of the total weight of the component A.

3. The two-component waterborne polyurethane antibacterial and mildewproof coating for the mildew proofing of the cigarette factories according to claim 2, which is characterized in that: the adding amount of the water-based zinc pyrithione in the component A is 3 percent of the total weight of the component A, the adding amount of the water-based 2-n-octyl-4-isothiazoline-3-ketone is 3.5 percent of the total weight of the component A, and the adding amount of the 3-iodo-2-propynyl butyl carbamate is 3 percent of the total weight of the component A.

4. The two-component waterborne polyurethane antibacterial and mildewproof coating for preventing mildew in a cigarette factory, according to claim 3, is characterized in that: the waterborne modified acrylic resin is waterborne hydroxyl functional polyacrylic acid, and the addition amount of the waterborne modified acrylic resin is 50 percent of the total weight of the component A.

5. The two-component waterborne polyurethane antibacterial and mildewproof coating for preventing mildew in a cigarette factory, according to claim 4, is characterized in that: the addition amount of the aqueous white slurry is 20 percent of the total weight of the component A, and the aqueous white slurry comprises the following components in percentage by weight:

6. the two-component waterborne polyurethane antibacterial and mildewproof coating for preventing mildew in a cigarette factory, according to claim 5, is characterized in that: the coating auxiliary materials comprise a first wetting agent, a defoaming agent, a second wetting agent, matting powder, kaolin, a leveling agent, a thickening agent and deionized water.

7. The two-component waterborne polyurethane antibacterial and mildewproof coating for preventing mildew in a cigarette factory, according to claim 6, is characterized in that: the first wetting agent is 140, the second wetting agent is propylene glycol, and the addition amount of each component of the coating auxiliary material respectively accounts for the total weight of the component A and is as follows:

8. the two-component aqueous polyurethane antibacterial and mildewproof coating for preventing mildew in a cigarette factory, according to any one of claims 1 to 7, is characterized in that: the curing agent is hydrophilic aliphatic polyisocyanate of Hexamethylene Diisocyanate (HDI).

9. A preparation method of a component A in a two-component waterborne polyurethane antibacterial and mildewproof coating for mildew prevention in a cigarette factory is characterized by comprising the following steps: the method comprises the following specific steps:

and step five, detecting, filtering and packaging.

10. The method for preparing the component A in the two-component waterborne polyurethane antibacterial and mildewproof coating for the cigarette factory according to claim 9 is characterized in that: the preparation method of the aqueous white slurry in the third step comprises the following steps:

and fourthly, adding the pigment into the third step, and dispersing for 30min at the speed of 1200r/min to obtain a qualified product with the fineness of not more than 30 microns.