PU odorless high-scratch-resistant extra-matte black finish paint and preparation method thereof

Abstract

The invention belongs to the technical field of coatings, and particularly relates to a PU odor-free high-scratch-resistance extra-matte black finish paint and a preparation method thereof. The PU odorless high-scratch-resistant extra-matte black finish paint is prepared from a main agent, a curing agent and a diluent, wherein the weight part ratio of the main agent to the curing agent to the diluent is 1: (0.5-0.7): (0.3-1); the main agent is prepared from the following components in parts by mass: 20 to 30 parts of polyester resin, 30 to 40 parts of CAB-381-2 liquid, 10 to 20 parts of black slurry, 11 to 23 parts of solvent and 1.9 to 13.1 parts of functional additive. According to the invention, through the change of the feeding sequence, the black slurry enters pores of the matting agent before the resin, so that the light process is simplified, relatively pure black light reflection is obtained, the blackness of the paint film is improved, and the black finish paint film with excellent matt degree and blackness and good performance is obtained.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and in particular relates to a PU odorless, highly scratch-resistant, extra-matte black topcoat and a preparation method thereof. Background Art

[0002] In modern interior and exterior decoration design, black is increasingly favored by designers and consumers due to its unique visual effects and high-end texture. Black can not only create a pure, elegant and restrained atmosphere, but is also suitable for spaces of various styles, such as simple modern, classic luxury. Therefore, the quality and performance of black paint is particularly important, which will directly affect the presentation of the overall decorative effect.

[0003] The traditional preparation process of polyurethane (PU) matte black topcoat usually involves high-speed dispersion of raw materials such as resin, black slurry dispersant, defoamer, anti-settling agent and solvent, and then adding matting powder to make the coating. The biggest defect of this type of product is that the blackness is not black enough, especially in the special matte products. In order to meet customers' high requirements for blackness, manufacturers often need to adjust the formula of black slurry or use special black slurry, which will inevitably increase production costs and may also affect production efficiency.

[0004] It is difficult to obtain a matte and dark black coating film performance under the premise of keeping the coating formula unchanged, not increasing the cost and not increasing the process complexity with the existing technology. Therefore, how to break through the performance limitations of traditional coatings and obtain a matte and black coating film with good performance without changing the existing formula, controlling costs and simplifying the production process has become a technical problem that needs to be solved urgently in the current coating industry. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a PU odorless, highly scratch-resistant, extra-matte black topcoat. The present invention allows the black slurry to enter the pores of the matting agent before the resin by changing the feeding sequence, while keeping the coating formula unchanged, the cost unchanged, and the process complexity unchanged, thereby simplifying the light process, obtaining a purer black light reflection, and improving the blackness of the paint film, thereby obtaining a black topcoat film with excellent matteness and blackness and good performance.

[0006] The technical solution adopted by the present invention to solve the above problems is as follows:

[0007] A PU odorless, highly scratch-resistant, extra-matte black topcoat is composed of a main agent, a curing agent and a diluent, wherein the weight ratio of the main agent, the curing agent and the diluent is main agent: curing agent: diluent = 1: 0.5-0.7: 0.3-1; the main agent comprises the following components calculated by mass: 20-30 parts of polyester resin, 30-40 parts of CAB-381-2 liquid, 10-20 parts of black slurry, 11-23 parts of solvent, and 1.9-13.1 parts of functional additives.

[0008] Furthermore, the polyester resin is Guangzhou Baohui PT461 odorless saturated polyester resin, which dries quickly at room temperature and has excellent wear resistance and scratch resistance.

[0009] Furthermore, the CAB-381-2 liquid is cellulose acetate butyrate from Eastman, USA.

[0010] Furthermore, the black slurry is at least one of D124-PF black slurry and M111-PF black slurry.

[0011] Preferably, the preparation method of the D124-PF black slurry includes: first adding 70 parts of phenolic resin, adding 1.5 parts of dispersant, 15 parts of propylene glycol methyl ether acetate, 10 parts of FW200 carbon black, and 3.5 parts of butyl acetate while stirring, and grinding to a fineness of ≤20μm to obtain D124-PF black slurry.

[0012] Preferably, the preparation method of the M111-PF black slurry includes: first adding 70 parts of phenolic resin, adding 1.5 parts of dispersant, 15 parts of propylene glycol methyl ether acetate, 10 parts of MA-100 carbon black, and 3.5 parts of butyl acetate while stirring, and grinding to a fineness of ≤20 μm to obtain M111-PF black slurry.

[0013] Preferably, the phenolic resin is CF-120; and the dispersant is BYK-166.

[0014] Furthermore, the functional additives include the following components calculated by mass: 0.5-0.8 parts of dispersant, 0-8 parts of matting powder, 1-3 parts of anti-settling agent, 0.1-0.4 parts of leveling agent, 0.1-0.4 parts of defoaming agent, and 0.2-0.5 parts of drying agent.

[0015] Furthermore, the solvent includes the following components calculated by mass: 3 to 5 parts of xylene, 5 to 10 parts of butyl acetate, and 3 to 8 parts of propylene glycol methyl ether acetate.

[0016] Furthermore, the dispersant is EFKA4010 modified polyurethane solution produced by Efka.

[0017] Furthermore, the matting powder is OK-520 matting powder produced by Evonik Degussa.

[0018] Furthermore, the anti-settling agent is 6900-X-20 polyamide wax slurry produced by Desbaron.

[0019] Furthermore, the leveling agent is TEGO-450 silicone solution.

[0020] Furthermore, the defoaming agent is BYK066N foam-breaking polymer polysiloxane solution produced by BYK Chemical.

[0021] Furthermore, the drying agent is American gas T-12.

[0022] Furthermore, the curing agent includes the following components calculated by mass: 35 to 50 parts of hexamethylene diisocyanate (HDI) trimer; 50 to 65 parts of butyl acetate.

[0023] Furthermore, the diluent includes the following components calculated by mass: 40 to 60 parts of butyl acetate; 20 to 40 parts of propylene glycol methyl ether acetate; and 0 to 15 parts of xylene.

[0024] The present invention provides a method for preparing the above-mentioned PU odorless, highly scratch-resistant, special matte black topcoat, comprising the following steps:

[0025] S1. The black slurry, solvent, and functional additive are evenly dispersed to a fineness of less than 20 μm, and then the polyester resin and CAB-381-2 liquid are evenly dispersed to obtain the main agent;

[0026] S2. The hexamethylene diisocyanate trimer and butyl acetate are evenly dispersed to obtain a curing agent;

[0027] S3. Evenly disperse butyl acetate, propylene glycol methyl ether acetate and xylene to prepare a diluent.

[0028] The present invention also provides the use of the above-mentioned PU odorless, highly scratch-resistant, extra-matte black topcoat, which is applied to surface finishing of wooden products.

[0029] The present invention has the following beneficial effects:

[0030] The present invention adopts a black-first process when preparing the black topcoat, that is, a process of premixing the matting agent and the black slurry, and then mixing the premix with the resin. In the black-first process, the matting agent is first mixed and dispersed with the black slurry, and the black slurry enters the pores of the matting agent. From the perspective of the light travel path, the light first penetrates the thin black coating on the outer layer of the matting agent, and then penetrates the matting agent itself, but cannot penetrate the black slurry in the pores of the matting agent. Therefore, the light will be directly reflected to the eyes of the observer, and the black topcoat shows a better blackness, which is a relatively pure black color to the naked eye.

[0031] The present invention allows the black slurry to enter the pores of the matting agent before the resin by changing the feeding sequence without changing the coating formula, increasing the cost and the complexity of the process, thereby simplifying the light process, obtaining purer black light reflection, improving the blackness of the paint film, and obtaining a black topcoat film with excellent matteness and blackness and good performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a comparison diagram of the blackness effect of the mixture prepared in Example 1 and Comparative Example 1 applied on a PVC film;

[0033] Figure 2 This is a comparison diagram of the blackness effect of the mixture prepared in Example 1 and Comparative Example 1 applied on black and white cardboard;

[0034] Figure 3 This is a comparison diagram of the blackness effect of the mixture prepared in Example 2 and Comparative Example 2 applied on a PVC film;

[0035] Figure 4 This is a comparison chart of the blackness effect of the mixture prepared in Example 2 and Comparative Example 2 applied on black and white cardboard. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, and are not limitations of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Unless otherwise specified, the test materials, reagents, methods and equipment used in the following examples are conventional test materials, reagents, methods and equipment in the technical field; unless otherwise specified, the test materials and reagents used in the following examples can be obtained from commercial sources. The quantitative tests in the following examples were all repeated three times, and the data are the average or average ± standard deviation of the three repeated experiments.

[0038] Embodiment 1:

[0039] Example 1 adopts the black first process to prepare the main agent, as shown in Table 1.

[0040] Table 1:

[0041]

[0042] Comparative Example 1:

[0043] Comparative Example 1 adopts the post-blackening process to prepare the main agent, as shown in Table 2.

[0044] Table 2:

[0045]

[0046]

[0047] Example 2

[0048] Compared with Example 1, Example 2 uses another M111-PF black slurry and adopts the first black process to prepare the main agent, as shown in Table 3.

[0049] Table 3:

[0050]

[0051] Comparative Example 2

[0052] Compared with Comparative Example 1, Comparative Example 2 uses another black paste M111-PF and a post-blackening process to prepare the main agent, as shown in Table 4.

[0053] Table 4:

[0054]

[0055] 40 parts of hexamethylene diisocyanate (HDI) trimer and 60 parts of butyl acetate are evenly dispersed to prepare a curing agent; 55 parts of butyl acetate, 35 parts of propylene glycol methyl ether acetate and 10 parts of xylene are evenly dispersed to prepare a diluent.

[0056] Keeping the fineness and viscosity of the main agent prepared in the embodiment and the comparative example consistent, start making the sample, mix the main agent prepared in the embodiment and the comparative example with the above-prepared curing agent in a mass ratio of 1:0.6, and then apply the resulting mixture on black and white cardboard and PVC film with a 20-micron scraper.

[0057] The coating results of Example 1 and Comparative Example 1 are as follows Figure 1 and Figure 2 The coating results of Example 2 and Comparative Example 2 are shown in Figure 3 and Figure 4 shown.

[0058] The glossiness of the mixture obtained in Example 1 and Comparative Example 1 applied on black and white cardboard and PVC film is 3.5° to 3.7°. Figure 1 and Figure 2It can be seen that Example 1 adopts the black-first process, that is, the matting agent and the black slurry are pre-mixed first, and then the pre-mixture is mixed with the resin. In the black-first process, the matting agent is first mixed and dispersed with the black slurry, and the black slurry enters the pores of the matting agent. From the perspective of the light travel path, the light first penetrates the thin black coating on the outer layer of the matting agent, and then penetrates the matting agent itself, but cannot penetrate the black slurry in the pores of the matting agent. Therefore, the light will be directly reflected to the observer's eyes, and the naked eye will see a relatively pure black color, and the obtained mixture shows a better blackness. ; Comparative Example 1 adopts a post-blackening process, that is, the matting agent and the resin are first mixed, and then mixed with the black slurry. In the post-blackening process, the matting agent is first mixed and dispersed with the resin, and the resin enters the pores of the matting agent. From the perspective of the light travel path, the light first penetrates the thin black coating on the outer layer of the matting agent, then penetrates the matting agent itself, and then penetrates the resin in the pores of the matting agent, and then is reflected to the observer's eyes. The whole travel process is complicated and the route is disordered. It is not pure black to the naked eye, and the blackness of the resulting mixture is obviously much worse.

[0059] After replacing another black paste in Example 2 and Comparative Example 2, the glossiness of the mixture obtained in Example 2 and Comparative Example 2 applied on black and white cardboard and PVC film was 3.0° to 3.3°. Figure 3 and Figure 4 It can be seen that Example 2 adopts the blackening process first, that is, the matting agent and the black slurry are pre-mixed, and then the pre-mixed mixture is mixed with the resin, and the resulting mixture exhibits better blackness; while Comparative Example 2 adopts the blackening process after, that is, the matting agent and the resin are first mixed, and then mixed with the black slurry, and the blackness of the resulting mixture is obviously much worse.

[0060] The main agent, curing agent and diluent prepared in the above Examples 1 to 2 and Comparative Examples 1 to 2 were mixed in a weight ratio of main agent: curing agent: diluent = 1: 0.6: 0.5 to prepare a black topcoat. The black topcoat was then sprayed on the surface of wooden furniture. The paint films of Examples 1 to 2 and Comparative Examples 1 to 2 were tested for performance according to GB / T 23997-2009 "Solvent-based polyurethane wood coatings for interior decoration and renovation" and GB 18581-2009 "Limits of harmful substances in solvent-based wood coatings for interior decoration and renovation materials". The test results are shown in Table 5 below.

[0061] Table 5:

[0062]

[0063]

[0064] The test results in Table 5 show that: under the condition that the coating formula remains unchanged, the cost does not increase, and the process complexity does not increase, the present invention changes the feeding order, allows the black slurry to enter the pores of the matting agent before the resin, simplifies the light process, obtains purer black light reflection, improves the blackness of the paint film, and obtains a black topcoat film with excellent matte and blackness and good performance.

[0065] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0066] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0067] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A PU clean odor, high scratch resistance, special matte black topcoat, characterized in that: The invention is composed of a main agent, a curing agent and a diluent, wherein the weight ratio of the main agent, the curing agent and the diluent is main agent: curing agent: diluent = 1: 0.5-0.7: 0.3-1; the main agent comprises the following components calculated by weight: 20-30 parts of polyester resin, 30-40 parts of CAB-381-2 liquid, 10-20 parts of black slurry, 11-23 parts of solvent and 1.9-13.1 parts of functional additives.

2. The PU clean odor, high scratch resistance, special matte black topcoat according to claim 1, characterized in that: The polyester resin is Guangzhou Baohui PT461 odorless saturated polyester resin.

3. The PU clean odor, high scratch resistance, special matte black topcoat according to claim 1, characterized in that: The black slurry is at least one of D124-PF black slurry and M111-PF black slurry.

4. The PU clean odor, high scratch resistance, special matte black topcoat according to claim 3, characterized in that: The functional additives include the following components calculated by mass: 0.5-0.8 parts of dispersant, 0-8 parts of matting powder, 1-3 parts of anti-settling agent, 0.1-0.4 parts of leveling agent, 0.1-0.4 parts of defoaming agent, and 0.2-0.5 parts of drying agent.

5. The PU clean odor, high scratch resistance, special matte black topcoat according to claim 4, characterized in that: The dispersant is Efka's EFKA4010 modified polyurethane solution; the matting powder is Evonik Degussa's TS-100 matting powder; the anti-settling agent is Desbaron's 6900-X-20 polyamide wax slurry; the leveling agent is Digo TEGO-450 silicone solution; the defoaming agent is BYK066N foam-breaking polymer polysiloxane solution; and the drying agent is American Gas T-12.

6. The PU clean odor, high scratch resistance, special matte black topcoat according to claim 4, characterized in that: The solvent comprises the following components calculated by mass: 3-5 parts of xylene, 5-10 parts of butyl acetate, and 3-8 parts of propylene glycol methyl ether acetate.

7. The PU clean odor, high scratch resistance, special matte black topcoat according to claim 6, characterized in that: The curing agent comprises the following components calculated by mass: 35-50 parts of hexamethylene diisocyanate trimer; 50-65 parts of butyl acetate.

8. The PU clean odor, high scratch resistance, special matte black topcoat according to claim 7, characterized in that: The diluent comprises the following components calculated by mass: 40 to 60 parts of butyl acetate; 20 to 40 parts of propylene glycol methyl ether acetate; and 0 to 15 parts of xylene.

9. A method for preparing the PU clean odor, high scratch resistance and special matte black topcoat as claimed in claim 8, characterized in that: The following steps are involved: S1. The black slurry, solvent, and functional additive are evenly dispersed to a fineness of less than 20 μm, and then the polyester resin and CAB-381-2 liquid are evenly dispersed to obtain the main agent; S2. The hexamethylene diisocyanate trimer and butyl acetate are evenly dispersed to obtain a curing agent; S3. Evenly disperse butyl acetate, propylene glycol methyl ether acetate and xylene to prepare a diluent.

10. An application of the PU clean odor, high scratch resistance, special matte black topcoat as claimed in any one of claims 1 to 8, characterized in that: Used for surface finishing of wooden products.

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