CN111961398A - High-hardness and quick-drying water-based bi-component filling clear primer and preparation method thereof - Google Patents

Abstract

The invention provides a high-hardness and quick-drying water-based double-component filling clear primer, which comprises the following components in percentage by weight of n (-NCO): uniformly mixing the component A and the component B according to the equivalent ratio of n (-OH) to 1.5-1.8; the component A comprises 75.0-80.0% of water-based acrylic emulsion, 0.8-1.0% of defoaming agent, 4.0-6.0% of film-forming additive, 3.0-6.0% of filling powder, 0.2-0.3% of wetting and leveling agent, 0.4-0.6% of anti-settling additive, 0.1-0.5% of thickening agent, 2.0-5.0% of grinding additive and 2.0-10.0% of water by weight percentage; the component B comprises the following components in percentage by weight: 30-40% of modified IPDI polyisocyanate and 60-70% of modified HDI polyisocyanate. the-OH in the primer emulsion component and the-NCO in the curing agent component have deep crosslinking reaction to generate urethane bonds, the coating film is compact, and the hardness of the paint film is improved. In addition, the minimum film forming temperature MFFT is more than or equal to 30 ℃, a faster drying speed is provided for a product system, and the requirement of changing oil into water in solid wood paint can be met; the invention also provides a preparation method of the water-based bi-component filling clear primer.

Description

High-hardness and quick-drying water-based bi-component filling clear primer and preparation method thereof

Technical Field

The invention relates to the technical field of paint production, in particular to a high-hardness and quick-drying water-based bi-component filling clear primer and a preparation method thereof.

Background

With the national higher and higher environmental requirements on the paint industry, the use of oil paint is forbidden in many provinces and cities. The water paint is favored in the market due to low pollution, low VOC emission and even no VOC emission.

The technical challenge of the water-based paint is getting bigger and bigger while the comprehensive oil-to-water change is carried out in the household industry and the paint chemical industry. In the solid wood furniture industry, the base material is mainly rubber wood, walnut wood and other multi-conduit wood, and the process is also mainly of a totally-closed transparent effect. The traditional oil paint process adopted in the prior art is mature, and the totally-enclosed effect can be achieved only by manufacturing one surface of two bottoms; most of the existing water-based paints can achieve a totally-enclosed effect only by three primers or even four primers, and the water-based paints are slow to dry and need to be baked for 8 to 12 hours at a temperature of between 35 and 40 ℃ normally, and the hardness of the water-based paints is not as good as that of oil.

Chinese patent with publication number CN110791193A discloses a water-based bi-component bright white paint, which is prepared from (2.5-4) by weight: 1, wherein the component A comprises the following raw materials in parts by weight: 50-60 parts of aqueous hydroxyl acrylic emulsion, 5-15 parts of water, 25-35 parts of titanium white slurry, 1-5 parts of high-density polyethylene wax emulsion, 1-3 parts of auxiliary agent, 0.1-0.2 part of ammonia neutralizer, 2-5 parts of dipropylene glycol butyl ether, 0.05-0.1 part of in-tank bactericide and 0.1-2 parts of thickening agent; the hydroxyl value of the water-based hydroxyl acrylate emulsion is 2.5-3.5, and the solid content is 60-80%; the component B is water-based silicon-based aliphatic polyisocyanate. The water-based bi-component bright white paint has high crosslinking density and high hardness, but the white paint is finish paint and needs to be verified in the aspect of totally-closed effect.

Therefore, how to provide a water-based primer with high hardness and quick drying and long activation period is a technical problem to be solved by the technical personnel in the field.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides the high-hardness and quick-drying water-based two-component filling clear primer, wherein-OH in a primer emulsion component and-NCO in a curing agent component are subjected to deep crosslinking reaction to generate urethane bonds, a coating film is compact, and the hardness of the paint film is improved. In addition, the first-grade dispersion hydroxyl acrylate emulsion is selected as a main component, the minimum film forming temperature MFFT is more than or equal to 30 ℃, and the molecular weight of the emulsion is higher, so that the fast drying speed is provided for a product system, and the requirement of changing oil into water in the solid wood paint can be met. The invention also provides a preparation method of the water-based bi-component filling clear primer.

In order to achieve the purpose, the invention provides the following technical scheme:

the high-hardness and quick-drying water-based two-component filling clear primer is characterized by comprising a component A and a component B, wherein the component A and the component B are mixed according to the formula of n (-NCO): n (-OH) is 1.5-1.8 in equivalent ratio and is uniformly mixed;

the component A comprises the following components in percentage by weight:

the component B comprises the following components in percentage by weight:

30 to 40 percent of modified IPDI polyisocyanate,

60-70% of modified HDI polyisocyanate.

As further description of the technical scheme of the invention, the water-based acrylic emulsion is a primary dispersion of polyacrylate containing hydroxyl, the hydroxyl is more than or equal to 3.0, and the minimum film-forming temperature MFFT is more than or equal to 30 ℃; the type of the aqueous acrylic emulsion is preferably AC2598 produced by Oubao.

In the primer, the first-level dispersoid high-hydroxyl acrylic emulsion is selected as the component A, and-OH in the emulsion component and-NCO in the curing agent component (the component B) are subjected to deep crosslinking reaction to generate urethane bonds, so that a compact coating film is obtained, and the hardness of the paint film is improved. In addition, the primary dispersion hydroxyl acrylate emulsion is selected as a main component, the minimum film forming temperature MFFT of the primary dispersion hydroxyl acrylate emulsion is more than or equal to 30 ℃, and the molecular weight of the emulsion is higher, so that the product system is dried at a higher speed.

Mixing the component A and the component B according to the formula of n (-NCO): and (3) uniformly mixing n (-OH) in an equivalent ratio of 1.5-1.8, adding a certain amount of water, adjusting to a proper construction viscosity, constructing, and drying to obtain a paint film with excellent physical and chemical properties and decorative properties.

As further description of the technical scheme of the invention, the defoaming agent comprises any one or more of polysiloxane, organic modified polysiloxane, fumed silica modified polyether siloxane or polyether siloxane, preferably one or more of BYK-024 produced by Bick Germany, BYK-028 and TEGO Airex 902W and TEGO Foamex 822 produced by Digao Germany, and is formed by mixing.

As a further description of the present invention, the coalescent includes one or both of dipropylene glycol butyl ether or propylene glycol butyl ether (DPNB) or propylene glycol butyl ether (PNB), preferably DPNB or PNB manufactured by Dow.

The film forming assistant is formed by combining and matching dipropylene glycol butyl ether (DPNB) and propylene glycol butyl ether (PNB), the film forming efficiency of the dipropylene glycol butyl ether (DPNB) is high, the drying rate of the propylene glycol butyl ether (PNB) is high, and the surface tension performance can be efficiently reduced. The DPNB and the PNB are matched, so that the water-based filling primer achieves good balance in the aspects of film forming property, wetting hole penetration property and drying speed.

As a further description of the solution of the invention, the filling powder consists of sand powders 376 and 378, the average particle sizes of which are respectively 25-35 μm and 44-55 μm; the sand powder 376 and 37 produced by Longhai chemical industry are preferred, the melting point of the sand powder combination is more than 150 ℃, and the specific gravity of the sand powder combination is 0.97 g/ml.

The primer disclosed by the invention selects the sand powder as the main filling powder, the specific gravity of the sand powder is 0.97g/ml, and is similar to that of common water-based varnish (about 1.05g/ml), so that the sand powder can be stably dispersed in a paint liquid and is not easy to settle and float; in addition, the main component of the sand powder is polypropylene, the polypropylene has excellent mechanical property and high rigidity strength, and the hardness performance of a paint film of the paint can be obviously improved.

According to the invention, two kinds of sand flour combinations with larger particle size difference are selected, and in the paint liquid film forming process, the large particles and the small particles are filled in a cross mode, so that tighter packing can be formed on the paint surface, and thus the paint film density of the paint is improved, and the performances such as transparency, hardness, filling property and the like are also improved more obviously.

As a further elaboration of the solution according to the invention, the wetting and leveling agent is a polyether modified siloxane, preferably TEGO Twin 4100, manufactured by digak, germany, or BYK 346, manufactured by BYK, germany.

As a further description of the technical solution of the present invention, the anti-settling aid is a polyamide wax, preferably tisibarone AQ600 or AQ 633E; the thickener is polyurethane associative thickener, preferably RM2020 and RM8W of Dow chemical or PUR44 and PUR64 of German Ming Ling; the grinding aid is zinc stearate slurry, and preferably MJ-555 or MJ-888 of the flower and fruit mountain brand is selected.

As a further description of the solution according to the invention, the modified IPDI polyisocyanate is a hydrophilic, water-dispersible isocyanate based on isophorone diisocyanate, preferably Bayhydur 401-60, produced by Bayer in Germany.

As a further description of the solution according to the invention, the modified HDI polyisocyanate is a hydrophilic, water-dispersible isocyanate based on hexamethylene diisocyanate, preferably Bayhydur XP 2655, produced by Bayer in Germany.

The invention also provides a preparation method of the water-based bi-component filling clear primer, which comprises the following steps:

(1) preparation of the component A:

s11, adding half of the total amount of the water-based acrylic emulsion in the component formula into a paint preparation cylinder, adding 1/3 mass of defoaming agent under the condition of stirring, and stirring and dispersing at the speed of 1500-1800r/min for 5 minutes to prepare pre-dispersion emulsion;

s12, slowly adding filling powder into the pre-dispersed emulsion, and dispersing at the speed of 1800 plus materials and 2000r/min to reach the specified fineness;

s13, slowly adding the remaining aqueous acrylic emulsion and the anti-settling auxiliary agent into a paint making cylinder at one time under the stirring condition;

s14, uniformly mixing the film-forming aid and water in advance, and slowly putting the mixture into a paint making cylinder under the stirring condition; then the residual 2/3 mass of the antifoaming agent, the wetting and leveling agent, the thickening agent and the grinding aid are sequentially and slowly put into a paint making cylinder and stirred for 10 minutes at the speed of 800-;

(2) preparation of the component B:

adding the modified IPDI polyisocyanate into the modified HDI polyisocyanate according to the weight percentage, and fully and uniformly stirring;

mixing the component A and the component B according to the formula of n (-NCO): and (3) uniformly mixing n (-OH) in an equivalent ratio of 1.5-1.8, and adding water to adjust the viscosity, thereby obtaining the water-based bi-component filling clear primer.

Based on the technical scheme, the invention has the following technical effects:

(1) according to the high-hardness and quick-drying water-based double-component filling clear primer, the water-based acrylic emulsion of the component A is a primary dispersion containing hydroxyl polyacrylate, and-OH in the emulsion component and-NCO in the curing agent component (the component B) are subjected to deep crosslinking reaction to generate urethane bonds, so that a compact coating film is obtained, and meanwhile, the hardness of the paint film is improved; in addition, the primary dispersion containing hydroxyl polyacrylate is selected as a main component, the minimum film forming temperature MFFT of the primary dispersion is more than or equal to 30 ℃, and the emulsion has higher molecular weight, so that the product system is dried at a higher speed.

(2) According to the high-hardness and quick-drying water-based double-component filling clear primer, the water-based curing agent selects the modified HDI type isocyanate blended and modified IPDI type isocyanate, and the advantages of quick drying, high crosslinking density and quick hardness rise of the modified HDI type isocyanate, and the advantages of low reaction activity and long opening time of the modified IPDI type isocyanate are fully combined, so that the characteristics of quick drying, high hardness, long activation period and difficult foaming are provided for products.

Detailed Description

In order that the invention may be more fully understood, reference will now be made to the specific embodiments illustrated. The invention provides a preferred embodiment. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

A high-hardness and quick-drying water-based two-component filling clear primer comprises a component A and a component B, wherein the component A and the component B are mixed according to the ratio of n (-NCO): n (-OH) is 1.5-1.8 in equivalent ratio and is uniformly mixed;

the component A comprises the following components in percentage by weight:

the component B comprises the following components in percentage by weight:

30 to 40 percent of modified IPDI polyisocyanate,

60-70% of modified HDI polyisocyanate.

Wherein, the components in the formula are selected as follows:

the water-based acrylic emulsion is a primary dispersion of polyacrylate containing hydroxyl, the hydroxyl is more than or equal to 3.0, and the minimum film-forming temperature MFFT is more than or equal to 30 ℃.

The primary dispersion of the hydroxyl-containing polyacrylate is selected as the water-based acrylic emulsion, and-OH in the emulsion component and-NCO in the curing agent component are subjected to deep crosslinking reaction to generate urethane bonds, so that a compact coating film is obtained, and meanwhile, the hardness of the paint film is improved; in addition, the primary dispersion containing hydroxyl polyacrylate is selected as a main component, the minimum film forming temperature MFFT of the primary dispersion is more than or equal to 30 ℃, and the emulsion has higher molecular weight, so that the product system is dried at a higher speed.

The defoaming agent comprises any one or more of polysiloxane, organic modified polysiloxane, fumed silica modified polyether siloxane or polyether siloxane.

The film forming assistant comprises one or two of dipropylene glycol butyl ether or propylene glycol butyl ether. The dipropylene glycol butyl ether (DPNB) has high film forming efficiency, the propylene glycol butyl ether (PNB) has high drying rate, and the surface tension performance can be effectively reduced. The DPNB and the PNB are matched, so that the water-based filling primer achieves good balance in the aspects of film forming property, wetting hole penetration property and drying speed.

The filling powders consist of flour 376 and 378, the average particle sizes of which are 25 to 35 μm and 44 to 55 μm, respectively.

Two kinds of sand flour combinations with larger grain diameter difference are selected, and in the paint liquid film forming process, the large and small grains are filled in a cross mode, so that tighter packing can be formed on the paint surface, and the paint film density of the paint is improved, and the performances such as transparency, hardness, filling property and the like are also improved more obviously.

The wetting and leveling agent is polyether modified siloxane, the anti-settling auxiliary agent is polyamide wax, the thickening agent is polyurethane associated thickening agent, and the polishing auxiliary agent is zinc stearate slurry.

The modified IPDI polyisocyanate is hydrophilic water dispersible isocyanate based on isophorone diisocyanate and has the advantages of low reaction activity and long open time. The modified HDI polyisocyanate is hydrophilic water-dispersible isocyanate based on hexamethylene diisocyanate, has the advantages of quick drying, high crosslinking density and quick hardness increase, provides quick drying and high hardness for products, and has the characteristics of long activation period and difficult foaming.

In the actual production process, the component A and the component B are prepared according to the following components in parts by weight and proportion:

(1) the raw materials (components) of the component A are shown in the table 1 in parts by weight and proportion.

TABLE 1 parts by weight and proportions of the first component materials (components)

The preparation method of the component A and the component B comprises the following steps:

s11, adding the hydroxyl acrylic emulsion-AC 2598 in the 1 st item in the component formula into a paint preparation cylinder, adding the defoaming agent 1-BYK-024 in the 2 nd item under the stirring condition, and stirring and dispersing at the speed of 1500-1800r/min for 5 minutes to prepare a pre-dispersion emulsion;

s12, slowly adding the filling powder 1-376 and the filling powder 2-380 of the items 3 and 4 in the pre-dispersed emulsion, and dispersing at the speed of 1800 plus materials 2000r/min until the fineness is less than 50 mu m;

s13, slowly adding the hydroxyl-containing acrylic emulsion-AC 2598 of the item 5 and the anti-settling auxiliary agent-AQ-600 of the item 6 into a paint preparing cylinder at one time under the stirring condition;

s14, adding the film-forming aid 1-PNB of item 7 and the film-forming aid 2-DPNB of item 8 into the deionized water of item 9 in advance, uniformly mixing, and slowly adding into a paint making cylinder under the stirring condition; then, slowly putting the polishing auxiliary agent-MJ-555, deionized water, a defoaming agent 2-TEGO Airex 902W, a wetting leveling agent-TEGO Twin 4100, a thickening agent 1-RM-2020 and a thickening agent 2-RM-8W into a paint making cylinder in turn, stirring for 10 minutes at the speed of 800 plus materials 1000r/min until the materials are completely and uniformly mixed, and filtering to obtain a component A;

(2) the raw materials (components) of the component B are shown in the table 2 in parts by weight and proportion.

TABLE 2 parts by weight and ratio of the second component raw materials (components)

Adding the modified IPDI polyisocyanate into the modified HDI polyisocyanate according to the weight percentage, and fully and uniformly stirring to obtain the component B.

The component A and the component B with different proportions are respectively mixed and cross-compounded, and the performance of the mixed water-based two-component filling clear primer is tested.

Example 1

Mixing the component A and the component B according to a ratio A, wherein the ratio A is as follows according to n (-NCO): and (3) uniformly mixing n (-OH) with the equivalent ratio of 1.6, adding water to adjust the viscosity to be suitable for construction, and standing for 5min to obtain the high-hardness quick-drying water-based bi-component filling clear primer.

Example 2

Mixing the component A and the component B according to a ratio of n (-NCO): and (3) uniformly mixing n (-OH) with the equivalent ratio of 1.6, adding water to adjust the viscosity to be suitable for construction, and standing for 5min to obtain the high-hardness quick-drying water-based bi-component filling clear primer.

Example 3

Mixing the component A with the component B and mixing the component B with the component A according to the formula that n (-NCO): and (3) uniformly mixing n (-OH) with the equivalent ratio of 1.6, adding water to adjust the viscosity to be suitable for construction, and standing for 5min to obtain the high-hardness quick-drying water-based bi-component filling clear primer.

Example 4

Mixing the component A with the component B and mixing the component B with the component B according to the formula that n (-NCO): and (3) uniformly mixing n (-OH) with the equivalent ratio of 1.6, adding water to adjust the viscosity to be suitable for construction, and standing for 5min to obtain the high-hardness quick-drying water-based bi-component filling clear primer.

Comparative example 1

The traditional aqueous two-component filling clear primer formula comprises the following components:

a component A:

acrylic emulsion XP 247080.0 percent containing hydroxyl,

defoaming agent 1 TEGO 8100.1%,

m-51.5 percent of anti-settling agent,

5.0 percent of filling powder silicon micro powder,

2.0 percent of film-forming additive 1 DPM,

2.0 percent of film-forming additive 1 DPNB,

6.8 percent of water and deionized water,

defoamer 2 TEGO902W 0.3%,

a wetting leveling agent TEGO 2450.3 percent,

thickener WT-105A 2.0%,

the sum of the raw materials in the component A is 100 percent.

B, component B:

propylene glycol methyl ether acetate (PMA): 20 percent of the total weight of the mixture,

modified HDI polyisocyanate (Bayhydur XP 2655): 80 percent of the total weight of the mixture,

the sum of the raw materials in the component B is 100 percent.

The preparation method of the component A comprises the following steps:

A. firstly, adding half of the total amount of the acrylic emulsion containing hydroxyl in the formula into a paint preparation cylinder, then adding part of defoaming agent under the condition of stirring, and dispersing for 5 minutes at the speed of 1500-.

B. Slowly adding all the filling powder into the pre-dispersed emulsion, and dispersing at the speed of 1800 plus materials and 2000 rpm until the fineness is less than 50 microns.

C. Slowly adding the rest of the acrylic emulsion containing hydroxyl into a paint preparing jar at one time under the stirring condition.

D. Uniformly mixing the film-forming assistant and water in advance, and slowly putting the mixture into a paint preparation cylinder under the stirring condition; and slowly and sequentially adding the rest defoaming agent, the wetting and leveling agent and the thickening agent into a paint preparation cylinder, stirring for 10 minutes at the speed of 800-1000 rpm until the components are completely and uniformly mixed, filtering and packaging.

The preparation method of the component B comprises the following steps:

adding propylene glycol monomethyl ether acetate (PMA) into the modified HDI polyisocyanate, and fully and uniformly stirring.

And uniformly mixing the component A and the component B according to the equivalent ratio of NCO/OH, namely n (-NCO) to n (-OH) to 1.6, adding a certain amount of water, adjusting to proper construction viscosity, and standing for 5min to obtain the conventional water-based two-component filling clear primer.

The high hardness, quick drying, aqueous two-component fill clear primer of examples 1-4, as well as the conventional aqueous two-component fill clear primer of comparative example 1, were tested. The test results are shown in Table 3.

Table 3 results of performance testing of the aqueous two-component filling clear primer of examples 1 to 4, comparative example 1

As can be seen from Table 3, the aqueous two-component filling clear primers of examples 1 to 4 all exhibited excellent properties in terms of fineness, storage stability, freeze-thaw resistance, workability, adhesion, hardness, drying time, and tube filling property; the drying time of the aqueous two-component filling clear primer of examples 1-4 was significantly less than the conventional aqueous two-component filling clear primer of comparative example 1 in terms of the measured drying time, and the catheter filling and paint pot life were also significantly better than the aqueous two-component filling clear primer of comparative example 1.

Thus, the high hardness, fast drying, aqueous two-component fill clear primer provided in examples 1-4 has a very fast drying rate, high hardness, high filling and a long activation time compared to the conventional aqueous two-component fill clear primer of comparative example 1. In addition, the coating films of the embodiments 1 to 4 have very good physical and chemical properties and mechanical properties, can well meet the requirements of solid wood furniture production and construction, and promote the process of changing oil into water in the solid wood furniture industry.

The foregoing is merely exemplary and illustrative of the structures of the present invention, which are described in some detail and detail, and are not to be construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications are possible without departing from the inventive concept, and such obvious alternatives fall within the scope of the invention.

Claims (9)

1. The high-hardness and quick-drying water-based two-component filling clear primer is characterized by comprising a component A and a component B, wherein the component A and the component B are mixed according to the formula of n (-NCO): n (-OH) is 1.5-1.8 in equivalent ratio and is uniformly mixed;

the component A comprises the following components in percentage by weight:

the component B comprises the following components in percentage by weight:

30 to 40 percent of modified IPDI polyisocyanate,

60-70% of modified HDI polyisocyanate.

2. The aqueous two-component filling clear primer according to claim 1, wherein the aqueous acrylic emulsion is a primary dispersion of hydroxyl-containing polyacrylate, the hydroxyl groups of which are not less than 3.0, and the minimum film-forming temperature MFFT is not less than 30 ℃.

3. The waterborne two-component filling clear primer according to claim 1, wherein the defoamer comprises any one or more of polysiloxane, organic modified polysiloxane, fumed silica modified polyether siloxane or polyether siloxane.

4. The waterborne two-component filling clear primer of claim 1, wherein the coalescent comprises one or both of dipropylene glycol butyl ether or propylene glycol butyl ether.

5. The two-component, aqueous filling primer according to claim 1, wherein the powder filler consists of sand powders 376 and 378, having average particle sizes of 25 to 35 μm and 44 to 55 μm, respectively.

6. The aqueous two-component filling clear primer according to claim 1, wherein the wetting and leveling agent is polyether modified siloxane, the anti-settling auxiliary agent is polyamide wax, the thickener is polyurethane associative thickener, and the polishing auxiliary agent is zinc stearate slurry.

7. The aqueous two-component filling clear primer according to claim 1, characterized in that the modified IPDI polyisocyanate is a hydrophilic water-dispersible isocyanate based on isophorone diisocyanate.

8. The aqueous two-component filling clear primer according to claim 1, characterized in that the modified HDI polyisocyanate is a hydrophilic water-dispersible isocyanate based on hexamethylene diisocyanate.

9. A process for the preparation of a water-borne two-component filling clear primer according to any one of claims 1 to 8, characterized in that it is prepared by the following steps:

(1) preparation of the component A:

s11, adding half of the total amount of the water-based acrylic emulsion in the component formula into a paint preparation cylinder, adding 1/3 mass of defoaming agent under the condition of stirring, and stirring and dispersing at the speed of 1500-1800r/min for 5 minutes to prepare pre-dispersion emulsion;

s12, slowly adding filling powder into the pre-dispersed emulsion, and dispersing at the speed of 1800 plus materials and 2000r/min to reach the specified fineness;

s13, slowly adding the remaining aqueous acrylic emulsion and the anti-settling auxiliary agent into a paint making cylinder at one time under the stirring condition;

s14, uniformly mixing the film-forming aid and water in advance, and slowly putting the mixture into a paint making cylinder under the stirring condition; then the residual 2/3 mass of the antifoaming agent, the wetting and leveling agent, the thickening agent and the grinding aid are sequentially and slowly put into a paint making cylinder and stirred for 10 minutes at the speed of 800-;

(2) preparation of the component B:

adding the modified IPDI polyisocyanate into the modified HDI polyisocyanate according to the weight percentage, and fully and uniformly stirring;

mixing the component A and the component B according to the formula of n (-NCO): and (3) uniformly mixing n (-OH) in an equivalent ratio of 1.5-1.8, and adding water to adjust the viscosity, thereby obtaining the water-based bi-component filling clear primer.