Matte water-based two-component finishing paint for rail transit interior and preparation method thereof

Abstract

The invention discloses a matte water-based two-component finish paint for rail transit interiors and a preparation method thereof.The finish paint is prepared from a component A and a component B. The component A is prepared from, by weight, 20-40 parts of 1 # water-based acrylic acid hydroxyl dispersion, 10-25 parts of 2 # water-based acrylic acid hydroxyl dispersion, 1-5 parts of trimethylbenzene, 1-5 parts of dipropylene glycol butyl ether, 0.1-1 part of wetting agent and 0.1-1 part of flatting agent; the water-based paint comprises the following components in parts by weight: 8-25 parts of water-based color paste, 10-20 parts of deionized water, 5-10 parts of talcum powder, 3-10 parts of a composite halogen-free flame retardant, 0.2-1 part of a defoaming agent, 0.5-1 part of an anti-aging agent, 0.1-3.0 parts of matt powder and 0.5-2 parts of a rheological agent. The component B comprises 40-60 parts of propylene glycol diacetate and 40-60 parts of a water-based isocyanate curing agent; through matching of soft and hard resin, toughness and hardness are both considered; the talcum powder is matched with the matt powder, so that the surface of the rail transit interior trimming panel is free of floating and good in matt property.

Description

Technical Field

[0001] The invention relates to the technical field of organic polymer coatings, in particular to a matte water-based two-component topcoat for rail transit interior decoration and a preparation method thereof. Background Art

[0002] Rail transit interior panels are widely used materials in subways, light rails and other transportation vehicles, and they mainly affect the weight, performance, function and quality of vehicles. With the continuous development of urban rail transit, the performance indicators of rail transit interior panels are becoming more and more important, and the requirements for flame retardancy, wear resistance and weather resistance are becoming higher and higher.

[0003] Matte sand texture is the most common topcoat film effect at present. The existing rail transit water-based topcoats with matte function supplied on the market generally have problems such as unstable gloss, rough particles on the surface, and uncertain flame retardancy, which seriously restricts the development of water-based coatings for rail transit vehicle interiors.

[0004] Chinese patent CN114736593A discloses a high-gloss water-based two-component topcoat and its preparation method and application. The topcoat includes two components, A and B; wherein the A component includes the following components in parts by weight: 15-40 parts of 1# water-based hydroxy acrylic dispersion, 10-25 parts of 2# water-based hydroxy acrylic dispersion, 1-5 parts of DPM, 1-5 parts of DPNB, 1-5 parts of trimethylbenzene, 0.1-1 parts of wetting agent, 0.1-1 parts of leveling agent, 10-30 parts of water-based color paste, 1-26.7 parts of deionized water, 0.2-1 parts of defoaming agent, 0.5-1 parts of anti-aging agent, and 0.5-2 parts of rheological agent; the B component includes the following components in parts by weight: PGDA 40-60 parts, 40-60 parts of water-based isocyanate curing agent, by effectively controlling the carbon chain length, molecular weight and polarity of the water-based hydroxy acrylic dispersion, thereby reducing the probability that water reacts with the -NCO group before the hydroxy acrylic resin, and then improving the compatibility of the hydroxy acrylic resin with the polyisocyanate, effectively reducing the demulsification phenomenon, and improving the glossiness of the topcoat; Chinese patent CN111518463A discloses a high-gloss water-based paint for rail transit and its preparation method and application, the paint comprises component A and component B with a weight ratio of 9:1, the component A comprises Covestro 2457 resin, Covestro 2695 resin, dispersant, defoamer, pigment, filler, film-forming aid, anti-settling agent, thickener, deionized water and water-based zinc stearate emulsion; by using resin A and resin B, the paint has the characteristics of high film-forming Tg, fast drying, high gloss and good leveling; the water-based zinc stearate emulsion can make the paint have good polishing performance after forming a paint film without reducing the gloss.

[0005] These existing technologies are improvements made for the preparation of high-gloss water-based two-component topcoats. However, in order to achieve a matte effect, the current water-based polyurethane matte topcoat for rail transit interiors often adds sand grain powder, which results in a small amount of coarse particles on the surface of the sand grain topcoat film, which is very rough; or the water-based hydroxy acrylic dispersion may cause local aggregation after mixing with the isocyanate curing agent due to the uneven particle size distribution of the dispersion, thereby causing floweriness, and the spraying process is prone to uneven film thickness. Therefore, there is a need to further improve the water-based two-component topcoat with a matte effect. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention provides a matte water-based two-component topcoat for rail transit interior and a preparation method thereof. The topcoat combines soft and hard resins to take into account both toughness and hardness, and combines talcum powder and matte powder to take into account both economy and feel, so that the surface does not bloom, has good leveling, is particle-free, has a flat surface, feels smooth, and has good flame retardant properties.

[0007] The technical solution of the present invention is:

[0008] The present invention provides a matte water-based two-component topcoat for rail transit interior, comprising components A and B, wherein the component A comprises the following components in parts by weight: 20-40 parts of a 1# water-based acrylic hydroxyl dispersion, 10-25 parts of a 2# water-based acrylic hydroxyl dispersion, 1-5 parts of trimethylbenzene, 1-5 parts of dipropylene glycol butyl ether, 0.1-1 parts of a wetting agent, 0.1-1 parts of a leveling agent, 8-25 parts of a water-based color paste, 10-20 parts of deionized water, 5-10 parts of talcum powder, 3-10 parts of a composite halogen-free flame retardant, 0.2-1 parts of a defoaming agent, 0.5-1 parts of an anti-aging agent, 0.1-3.0 parts of a matte powder, and 0.5-2 parts of a rheological agent; wherein the 1# water-based acrylic hydroxyl dispersion is Covestro 2646; the 2# water-based acrylic hydroxyl dispersion is Qirun New Material AH239;

[0009] The B component comprises the following components in parts by weight: 40-60 parts of propylene glycol diacetate and 40-60 parts of water-based isocyanate curing agent.

[0010] Furthermore, the weight ratio of the 1# aqueous acrylic hydroxyl dispersion to the 2# aqueous acrylic hydroxyl dispersion is 7:5.

[0011] Further, the A component includes the following components in parts by weight: 28 parts of 1# water-based hydroxy acrylic dispersion, 20 parts of 2# water-based hydroxy acrylic dispersion, 1.5 parts of dipropylene glycol butyl ether, 3 parts of trimethylbenzene, 0.5 parts of wetting agent, 0.2 parts of leveling agent, 17 parts of water-based color paste, 10.1 parts of deionized water, 0.2 parts of defoaming agent, 8 parts of talc, 8 parts of composite halogen-free flame retardant, 0.8 parts of anti-aging agent, 1.5 parts of matte powder, and 1.2 parts of rheological agent;

[0012] The B component includes the following components in parts by weight: 50 parts of propylene glycol diacetate, 50 parts of water-based isocyanate curing agent

[0013] Furthermore, the wetting agent is BYK-254, BYK-4100 or BYK-278; the leveling agent is BYK-331, BYK-381 or BYK-3560.

[0014] Furthermore, the defoaming agent is Digo 901W, Digo 902W or Digo 810.

[0015] Furthermore, the composite halogen-free flame retardant in the A component is Jiaxing Binghuo New Material SW-53 composite flame retardant.

[0016] Furthermore, the anti-aging agent is BASF 400W, Everlight AQ1 or Everlight AQ9.

[0017] Furthermore, the rheological agent is 3030, 3060 or 1191.

[0018] The present invention also provides a method for preparing a matte water-based two-component topcoat for rail transit interior decoration, comprising the following steps:

[0019] S1, sequentially adding the formulated amount of 1# aqueous hydroxylated acrylic acid dispersion and 2# aqueous hydroxylated acrylic acid dispersion into a reactor, stirring, to obtain a feed solution 1;

[0020] S2, adding the formulated amount of wetting agent, leveling agent, defoaming agent and anti-aging agent to the liquid 1 obtained in step S1 while stirring, stirring at a speed of 300-600 rpm / min for 5-10 minutes to obtain liquid 2;

[0021] S3, adding the formulated amount of dipropylene glycol butyl ether and trimethylbenzene to the feed solution 2 obtained in step S2 while stirring, and stirring at a rate of 300-600 rpm / min for 5-10 minutes to obtain feed solution 3;

[0022] S4, adding the formulated amount of talcum powder, water-based color paste, deionized water, composite halogen-free flame retardant and matte powder to the liquid 3 obtained in step S3, stirring at a rate of 600-800 rpm / min for 30 minutes, then adding the rheological agent, stirring at a rate of 600-800 rpm / min for 20 minutes, to obtain component A;

[0023] S5. Add the formulated amount of propylene glycol diacetate and dehydrating agent into a container, add the aqueous isocyanate curing agent after 10 minutes, and stir at 300-600 rpm for 15 minutes to obtain component B.

[0024] The present invention also provides a method for using a matte water-based two-component topcoat for rail transit interiors, comprising mixing component A, component B and deionized water in a weight ratio of 5:1:(0.2-0.6), and then coating the mixture on the surface of the rail transit interior.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The matte water-based two-component topcoat prepared by the present invention is used for rail transit vehicle interior panels, has excellent construction performance, excellent interlayer adhesion, and the adhesion is maintained at level 0. It has good water resistance, acid resistance, alkali resistance, stain resistance, butanone resistance and other ultra-high resistance. In terms of physical performance, it has good hardness and toughness, and excellent aging resistance. The addition of a composite halogen-free flame retardant makes the topcoat have strong flame retardancy while taking into account matte properties. The fire resistance meets the EU EN45545 standard and can meet the various requirements of rail transit interior panels.

[0027] 2. The 1# water-based acrylic hydroxy dispersion used in the present invention is Covestro 2646, which has a small molecular weight, good flexibility and excellent aging resistance. The 2# water-based hydroxy acrylic dispersion used is Qirun new material, which dries quickly, has high hardness, excellent aging resistance and high comprehensive performance. By using two kinds of soft and hard resins, both toughness and hardness are taken into account. In addition, the combination of talcum powder and matte powder makes the topcoat feel better, the surface does not flower, the matte property is better, and the gloss Gs=50-60% / 60°. DETAILED DESCRIPTION

[0028] The experimental methods in the following examples of the present invention, where no specific conditions are specified, are usually carried out under conventional conditions or under conditions recommended by the manufacturers. The various commonly used chemical reagents used in the examples are all commercially available products.

[0029] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0030] The present invention is further described in the following examples, but the examples are not intended to limit the scope of protection of the present invention.

[0031] In order to achieve a matte effect, water-based polyurethane matte topcoats for rail transit interiors often add sand grain powder, which results in a small amount of coarse particles on the surface of the sand grain topcoat film, which is very rough; or the water-based hydroxy acrylic dispersion has an uneven particle size distribution, which may lead to local aggregation after mixing with isocyanate curing agent, causing floweriness, and the spraying process is prone to uneven film thickness.

[0032] The preparation formula of the matte water-based two-component topcoat for rail transit interior decoration of Examples 1-3 of the present invention is shown in Table 1 below:

[0033] Table 1 Formulation of matte water-based two-component topcoat for rail transit interior

[0034]

[0035]

[0036] The preparation of the matte water-based two-component topcoat for rail transit interior of Examples 1-3 comprises the following steps:

[0037] S1, sequentially adding the formulated amount of 1# aqueous hydroxylated acrylic acid dispersion and 2# aqueous hydroxylated acrylic acid dispersion into a reactor, stirring, to obtain a feed solution 1;

[0038] S2, adding the formulated amount of wetting agent, leveling agent, defoaming agent and anti-aging agent to the liquid 1 obtained in step S1 while stirring, stirring at a speed of 300-600 rpm / min for 5-10 minutes to obtain liquid 2;

[0039] S3, adding the formulated amount of DPNB and trimethylbenzene to the feed solution 2 obtained in step S2 while stirring, and stirring at a rate of 300-600 rpm / min for 5-10 minutes to obtain feed solution 3;

[0040] S4, adding the formulated amount of ultrafine talcum powder, water-based color paste, deionized water, composite halogen-free flame retardant and matte powder to the liquid 3 obtained in step S3, stirring at a rate of 600-800 rpm / min for 30 minutes, then adding the rheological agent, stirring at a rate of 600-800 rpm / min for 20 minutes, to obtain component A;

[0041] S5. Add the formulated amount of PGDA and dehydrating agent into a clean container. After 10 minutes, add the water-based isocyanate curing agent and stir at 300-600 rpm for 15 minutes to obtain component B.

[0042] The present invention uses 1# water-based acrylic hydroxyl dispersion Covestro 2646, which has a small molecular weight, good bending, good compatibility with component B, is not easy to aggregate, and has excellent aging resistance. At the same time, 2# water-based hydroxyl acrylic dispersion Qirun new material AH239 has the advantages of excellent leveling performance, fast drying, high hardness, excellent chemical resistance, strong comprehensive performance, etc.; preferably, the two are matched in a weight ratio of 7:5, and the two soft and hard resins are matched, taking into account toughness and hardness, so that acid resistance, alkali resistance, and weather resistance are all excellent; preferably, talcum powder and matte powder are matched in a mass ratio of (10-50): (1-3) to avoid the influence of the difference in the flow and evaporation speed of the solvent, so as to reduce the drift phenomenon of the matte powder in the paint film, maintain smoothness, and have a matte effect while maintaining a more uniform surface, so that the topcoat has a better feel, the surface does not flower, and the matte property is better. The matte water-based two-component topcoat of the present invention is applied to the surface of the rail transit interior when in use. Compared with the spray painting process, the thickness is more evenly controlled, reducing the risk of flower.

[0043] In the above embodiment, the talc powder may also be ground talc powder and micro-fine talc powder, preferably ultra-fine talc powder with a mesh size of 1250 or more, which has a smaller particle size and is easier to mix evenly.

[0044] In the above embodiment, the matte powder is preferably Tosoh 1011, which has good dispersibility and high transparency, and is also compatible with the resin, solvent and other components in the topcoat. It is not prone to problems such as stratification, precipitation, and flocculation, and can be used for matting without damaging the base color of the coating.

[0045] In the above embodiments, the water-based isocyanate curing agent is a coating curing agent with good water resistance and chemical resistance, and both HDI and IPDI types are available in the market.

[0046] Comparative Example 1

[0047] The difference between this comparative example and Example 1 is that the 1# aqueous acrylic hydroxyl dispersion used is different, that is, 1# aqueous acrylic hydroxyl dispersion Wanhua 2033 is used instead of 1# aqueous acrylic hydroxyl dispersion Covestro 2646, and the rest is exactly the same as Example 1.

[0048] Comparative Example 2

[0049] The difference between this comparative example and Example 1 is that the 2# aqueous acrylic hydroxyl dispersion used is different. The 2# aqueous acrylic hydroxyl dispersion Wanhua 2072 is used instead of the 2# aqueous acrylic hydroxyl dispersion Qirun New Material AH239. The rest is exactly the same as Example 1.

[0050] Comparative Example 3

[0051] The difference between this comparative example and Example 1 is that the 1# aqueous acrylic hydroxyl dispersion used replaces the 2# aqueous acrylic hydroxyl dispersion, wherein the aqueous acrylic hydroxyl dispersion Covestro 2646 replaces the 2# aqueous acrylic hydroxyl dispersion Qirun New Material AH239, and the rest is exactly the same as Example 1.

[0052] Comparative Example 4

[0053] The difference between this comparative example and Example 1 is that the weight ratio of 1# aqueous acrylic hydroxyl dispersion to 2# aqueous acrylic hydroxyl dispersion in component A is 5:7, and the rest is exactly the same as Example 1.

[0054] Comparative Example 5

[0055] The difference between this comparative example and Example 1 is that the mass ratio of talc powder to matte powder in component A is 4.5:5, which is not within the range of (10-50):(1-3). The rest is exactly the same as Example 1.

[0056] Comparative Example 6

[0057] The difference between this comparative example and Example 1 is that the type of composite halogen-free flame retardant is different. This comparative example uses Jiaxing Binghuo new material flame retardant SP-8599.

[0058] Test Example 1: Performance Test

[0059] 1. Test object: The matte water-based two-component topcoat obtained in Examples 1-3 and Comparative Examples 1-6 was tested by mixing component A, component B and deionized water in a weight ratio of 5:1:(0.2-0.6).

[0060] 2. Test methods and test results: The test results are shown in Tables 2-1 and 2-2:

[0061] Table 2-1 Performance test results

[0062]

[0063]

[0064] Table 2-2 Performance test results

[0065]

[0066]

[0067] It can be seen from Table 2-1 that the matte water-based two-component topcoat prepared in Examples 1-3 of the present invention has excellent interlayer adhesion, and the adhesion is maintained at level 0. In terms of resistance, it has excellent water resistance, acid resistance, alkali resistance, stain resistance and other ultra-high resistance. In terms of physical performance, the hardness and toughness are very good. After the MEK wiping test, after 50 wipes, the appearance and hardness of the coating film are immediately compared with those in the adjacent area, and there is no obvious change. It has excellent aging resistance and strong flame retardancy. The fire resistance meets the EU EN45545 standard, and the surface is flat and smooth with good matte properties.

[0068] It can be seen from Table 2-2 that the performance of the topcoat prepared in Comparative Examples 1-6 is not as good as that prepared in Example 1-3. Among them, Comparative Examples 1-4 are because the types of the 1# water-based hydroxy acrylic dispersion and the 2# water-based hydroxy acrylic dispersion used or the ratio of the two have changed, and other commercially available dispersion types such as 2033 Wanhua and 2072 Wanhua dispersions are used instead. The dispersion particle size distribution may be different in width and cannot be matched to achieve a complementary effect, thereby causing the performance of the topcoat to deteriorate. The 1# water-based acrylic hydroxy dispersion Covestro 2646 used in the present invention has a small molecular weight, good flexibility, and excellent aging resistance. The 2# water-based hydroxy acrylic dispersion used The base acrylic dispersion is Qirun new material dispersion AH239, which dries quickly, has high hardness, excellent chemical resistance and high comprehensive performance. By using these two soft and hard resins in a weight ratio of 7:5, the topcoat has both toughness and hardness, so that various performances are better; in comparative example 5, the mass ratio of matte powder to talcum powder is not in the range of (10-50): (1-3), and the amount of matte powder added is relatively large, which may be offset by the influence of the solvent, resulting in particles in the topcoat and an uneven surface; in comparative example 6, the flame retardant SP-8599 is used, which has poor compatibility with the water-based resin system, resulting in poor flame retardant effect of the topcoat.

[0069] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A matte water-based two-component topcoat for rail transit interior, characterized in that: It comprises components A and B, wherein component A comprises the following components in parts by weight: 20-40 parts of 1# water-based acrylic hydroxyl dispersion, 10-25 parts of 2# water-based acrylic hydroxyl dispersion, 1-5 parts of trimethylbenzene, 1-5 parts of dipropylene glycol butyl ether, 0.1-1 parts of wetting agent, 0.1-1 parts of leveling agent, 8-25 parts of water-based color paste, 10-20 parts of deionized water, 5-10 parts of talcum powder, 3-10 parts of composite halogen-free flame retardant, 0.2-1 parts of defoaming agent, 0.5-1 parts of anti-aging agent, 0.1-3.0 parts of matte powder, and 0.5-2 parts of rheological agent; wherein, the 1# water-based acrylic hydroxyl dispersion is Covestro 2646; the 2# water-based acrylic hydroxyl dispersion is Qirun New Material AH239; The B component comprises the following components in parts by weight: 40-60 parts of propylene glycol diacetate and 40-60 parts of water-based isocyanate curing agent.

2. The matte water-based two-component topcoat for rail transit interior according to claim 1, characterized in that: The weight ratio of the 1# aqueous acrylic hydroxyl dispersion to the 2# aqueous acrylic hydroxyl dispersion is 7:

5.

3. The matte water-based two-component topcoat for rail transit interior according to claim 1, characterized in that: The component A comprises the following components in parts by weight: 28 parts of 1# water-based hydroxy acrylic dispersion, 20 parts of 2# water-based hydroxy acrylic dispersion, 1.5 parts of dipropylene glycol butyl ether, 3 parts of trimethylbenzene, 0.5 parts of wetting agent, 0.2 parts of leveling agent, 17 parts of water-based color paste, 10.1 parts of deionized water, 0.2 parts of defoaming agent, 8 parts of talc, 8 parts of composite halogen-free flame retardant, 0.8 parts of anti-aging agent, 1.5 parts of matte powder, and 1.2 parts of rheological agent; The B component includes the following components in parts by weight: 50 parts of propylene glycol diacetate and 50 parts of water-based isocyanate curing agent.

4. The matte water-based two-component topcoat for rail transit interior according to claim 1, characterized in that: The wetting agent is BYK 254, BYK 4100 or BYK 278; the leveling agent is BYK-331, BYK-381 or BYK-3560.

5. The matte water-based two-component topcoat for rail transit interior according to claim 1, characterized in that: The defoaming agent is Digo 901W, Digo 902W or Digo 810.

6. The matte water-based two-component topcoat for rail transit interior according to claim 1, characterized in that: The composite halogen-free flame retardant in the A component is Jiaxing Binghuo New Material SW-53 composite flame retardant.

7. The matte water-based two-component topcoat for rail transit interior according to claim 1, characterized in that: The anti-aging agent is BASF 400W, Yongguang AQ1 or Yongguang AQ9.

8. The matte water-based two-component topcoat for rail transit interior according to claim 1, characterized in that: The rheological agent is 3030, 3060 or 1191.

9. A method for preparing a matte water-based two-component topcoat for rail transit interior decoration according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1, sequentially adding the formulated amount of 1# aqueous hydroxylated acrylic acid dispersion and 2# aqueous hydroxylated acrylic acid dispersion into a reactor, stirring, to obtain a feed solution 1; S2, adding the formulated amount of wetting agent, leveling agent, defoaming agent and anti-aging agent to the liquid 1 obtained in step S1 while stirring, stirring at a speed of 300-600 rpm / min for 5-10 minutes to obtain liquid 2; S3, adding the formulated amount of dipropylene glycol butyl ether and trimethylbenzene to the feed solution 2 obtained in step S2 while stirring, and stirring at a rate of 300-600 rpm / min for 5-10 minutes to obtain feed solution 3; S4, adding the formulated amount of talcum powder, water-based color paste, deionized water, composite halogen-free flame retardant and matte powder to the liquid 3 obtained in step S3, stirring at a rate of 600-800 rpm / min for 30 minutes, then adding the rheological agent, stirring at a rate of 600-800 rpm / min for 20 minutes, to obtain component A; S5. Add the formulated amount of propylene glycol diacetate and dehydrating agent into a container, add the water-based isocyanate curing agent after 10 minutes, and stir at 300-600 rpm for 15 minutes to obtain component B.

10. A method for using the matte water-based two-component topcoat for rail transit interiors as claimed in any one of claims 1 to 8, characterized in that: Mix component A, component B and deionized water in a weight ratio of 5:1:(0.2-0.6), and then apply them on the surface of rail transit interior.

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