PU (polyurethane) anti-scratch self-repairing ultra-matte transparent finish paint and preparation method thereof

Abstract

The invention discloses a PU (polyurethane) anti-scratch self-repairing ultra-matte transparent finish paint and a preparation method thereof. The PU anti-scratch self-repairing ultra-matte transparent finish paint comprises a component A and a component B, the component A comprises the following raw materials: polycarbonate resin; a wetting dispersant; a leveling agent; a defoaming agent; xylene; matt powder; ethyl acetate; propylene glycol methyl ether acetate; n-butyl acetate; the component B comprises the following raw materials: an HDI curing agent; the PU anti-scratch self-repairing ultra-matte transparent finish paint is glossy, ultra-matte, free of fingernail scratch and excellent in scratch resistance.

Description

Technical Field

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

[0002] Modern furniture is increasingly pursuing personalization, especially high-end customized furniture, which also has high requirements for coating, especially certain requirements for paint film gloss and scratch resistance. After the existing PU topcoat is painted and dried, it is easy to leave obvious bright marks on the surface of the paint film when scratched with a fingernail. The scratch resistance is poor and cannot meet the requirements of modern furniture coating. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a PU scratch-resistant self-repairing extra-matte transparent topcoat and a preparation method thereof. The PU scratch-resistant self-repairing extra-matte transparent topcoat has an extra-matte gloss, leaves no marks from fingernail scratches, and has excellent scratch resistance.

[0004] The above technical objectives of the present invention are achieved through the following technical solutions:

[0005] A PU scratch-resistant self-repairing extra-matte transparent topcoat comprises a component A and a component B; the component A comprises the following raw materials: polycarbonate resin; a wetting and dispersing agent; a leveling agent; a defoaming agent; xylene; matting powder; ethyl acetate; propylene glycol methyl ether acetate; and n-butyl acetate; the component B comprises the following raw materials: an HDI curing agent and n-butyl acetate.

[0006] Preferably, the component A includes the following raw materials in parts by weight: polycarbonate resin: 25-35 parts; wetting and dispersing agent: 0.2-1.0 parts; leveling agent: 0.5-2 parts; defoaming agent: 0.2-0.5 parts; xylene: 10-15 parts; matte powder: 5-8 parts; ethyl acetate: 15-25 parts; propylene glycol methyl ether acetate: 8-15 parts; n-butyl acetate: 6-20 parts; the component B includes the following raw materials in parts by weight: HDI curing agent: 20-40 parts; n-butyl acetate: 60-80 parts.

[0007] Preferably, the invention further comprises a C component, which comprises the following raw materials in parts by weight: n-butyl acetate: 45-65 parts; propylene glycol methyl ether acetate: 20-30 parts; and isopropyl alcohol: 10-20 parts.

[0008] Preferably, the weight ratio of component A, component B and component C is 1:(0.1-0.3):(0.5-0.8).

[0009] Preferably, the fineness of component A is ≤25um.

[0010] Preferably, the viscosity of component A is 300-500 mPa·s / 25°C.

[0011] A method for preparing the above-mentioned PU scratch-resistant self-repairing special matte transparent topcoat comprises the following steps:

[0012] (1) Preparation of Component A: Polycarbonate resin, wetting and dispersing agent, defoaming agent, leveling agent, and xylene are mixed and dispersed for the first time, matting powder is added and dispersed for the second time, ethyl acetate, n-butyl acetate, and propylene glycol methyl ether acetate are added and dispersed for the third time, and the viscosity is adjusted to obtain Component A;

[0013] (2) preparing component B: mixing HDI curing agent and n-butyl acetate, heating and then keeping the temperature, cooling and discharging to obtain the component B;

[0014] (3) Component A and component B are mixed to form a mixture.

[0015] Preferably, the method further comprises the step (4) of mixing n-butyl acetate, propylene glycol methyl ether acetate and isopropyl alcohol and then mixing the mixture with the mixture in step (3).

[0016] Preferably, in step (1), the rotation speed of the first dispersion and the third dispersion are both 600-800 r / min, and the dispersion time is 5-10 min; the rotation speed of the second dispersion is 1200-1500 r / min, and the dispersion time is 10-15 min.

[0017] Preferably, in step (2), the temperature after heating is 60-80° C., and the insulation time is 20-50 minutes.

[0018] The beneficial effects of the present invention are:

[0019] (1) The PU anti-scratch self-repairing special matte transparent topcoat of the present invention uses a specific polycarbonate resin and matte powder. The paint film made of polycarbonate resin has a balance of elasticity and hardness, and the matte powder used has a certain smoothness. It can play a self-repairing role at the moment of scratching by nails, so it can achieve the effect of no trace of finger scratches and has excellent scratch resistance.

[0020] (2) The PU scratch-resistant self-repairing extra-matte transparent topcoat of the present invention leaves no marks when scratched by nails, has an extra-matte gloss (less than 3°), and has high transparency; during construction, it has good leveling and is easy to spray. DETAILED DESCRIPTION

[0021] The present invention will be further described below with reference to specific embodiments.

[0022] Example 1-5:

[0023] A method for preparing a PU scratch-resistant self-repairing extra-matte transparent topcoat comprises the following steps:

[0024] (1) Preparation of Component A: Polycarbonate resin, wetting and dispersing agent, defoaming agent, leveling agent, and xylene were mixed and dispersed at 700 r / min for 8 min, matting powder was added and dispersed at 1300 r / min for 12 min, ethyl acetate, n-butyl acetate, and propylene glycol methyl ether acetate were added and dispersed at 700 r / min for 8 min, and dispersed to a fineness of ≤25 μm. After adjusting the viscosity to 400 mPa·s / 25°C, Component A was obtained;

[0025] (2) Preparation of Component B: HDI curing agent and n-butyl acetate were mixed, stirred and dispersed for 30 minutes, heated to 70°C and kept warm for 30 minutes, cooled and discharged to obtain the Component B;

[0026] (3) preparing component C: mixing n-butyl acetate, propylene glycol methyl ether acetate and isopropyl alcohol to obtain component C;

[0027] (4) Component A, component B, and component C are mixed to prepare the PU scratch-resistant self-repairing matte transparent topcoat.

[0028] The reagents used in Examples 1-5 are all commercially available, among which the polycarbonate resin is produced by Dongguan Zuorong Chemical Co., Ltd. and has a product model of 9#; the wetting and dispersing agent is produced by BASF Europe, Germany, and has a product model of EFKA4010; the leveling agent is produced by Shanghai Tiger Polymer Technology Co., Ltd. and has a product model of A255; the defoaming agent is produced by BYK, Germany, and has a product model of BYK 141; the matte powder is produced by Guangdong Silika New Materials Co., Ltd. and has a product model of C903; the HDI curing agent is produced by Covestro, Germany, and has a product model of N3390;

[0029] The amounts of component A, component B, and component C in the PU scratch-resistant self-repairing extra-matte transparent topcoat of Examples 1-5 and the weight ratios of component A, component B, and component C are shown in Table 1;

[0030] Table 1: Amount and weight ratio of each component in the PU scratch-resistant self-repairing special matte transparent topcoat of Examples 1-5

[0031]

[0032] Test example:

[0033] The PU scratch-resistant self-repairing extra matte transparent topcoat prepared in Examples 1-5 was subjected to performance tests with commercially available PU extra matte clear topcoat A (elastic resin system) and PU extra matte clear topcoat B (hydroxy acrylic system). The results are shown in Table 2.

[0034] Table 2. Performance test results

[0035]

[0036]

[0037] As can be seen from Table 2, the PU scratch-resistant self-repairing extra matte transparent topcoat prepared by the present invention has a surface drying time of ≤20 min, a glossiness of less than 3°, a uniform arrangement of matte powder, an adhesion of up to level 1, a flexibility of up to 1 mm, a smooth feel, and excellent scratch resistance of the paint film. There are no marks left by nail scratches and the paint film is not damaged. The PU scratch-resistant self-repairing extra matte transparent topcoat of the present invention is superior to the commercially available PU extra matte clear topcoat A and PU extra matte clear topcoat B in terms of paint film scratch resistance.

[0038] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A PU scratch-resistant self-repairing matte transparent topcoat, characterized by: The invention comprises component A and component B; the component A comprises the following raw materials: polycarbonate resin; wetting and dispersing agent; leveling agent; defoaming agent; xylene; matting powder; ethyl acetate; propylene glycol methyl ether acetate; n-butyl acetate; the component B comprises the following raw materials: HDI curing agent; n-butyl acetate.

2. The PU scratch-resistant self-repairing special matte transparent topcoat according to claim 1, characterized in that: The component A comprises the following raw materials in parts by weight: Polycarbonate resin: 25-35 parts; Wetting and dispersing agent: 0.2-1.0 parts; Leveling agent: 0.5-2 parts; Defoaming agent: 0.2-0.5 parts; Xylene: 10-15 parts; Matt powder: 5-8 parts; Ethyl acetate: 15-25 parts; Propylene glycol methyl ether acetate: 8-15 parts; n-Butyl acetate: 6-20 parts; The component B comprises the following raw materials in parts by weight: HDI curing agent: 20-40 parts; n-Butyl acetate: 60-80 parts.

3. The PU scratch-resistant self-repairing special matte transparent topcoat according to claim 1, characterized in that: The third component also includes the following raw materials in parts by weight: n-Butyl acetate: 45-65 parts; Propylene glycol methyl ether acetate: 20-30 parts; Isopropyl alcohol: 10-20 parts.

4. The PU scratch-resistant self-repairing matte transparent topcoat according to claim 3, characterized in that: The weight ratio of the component A, the component B and the component C is 1:(0.1-0.3):(0.5-0.8).

5. The PU scratch-resistant self-repairing special matte transparent topcoat according to claim 1, characterized in that: The fineness of the component A is ≤25um.

6. The PU scratch-resistant self-repairing special matte transparent topcoat according to claim 1, characterized in that: The viscosity of the component A is 300-500 mPa·s / 25°C.

7. A method for preparing the PU scratch-resistant self-repairing extra-matte transparent topcoat according to any one of claims 1 to 6, characterized in that: The following steps are involved: (1) Preparation of Component A: Polycarbonate resin, wetting and dispersing agent, defoaming agent, leveling agent, and xylene are mixed and dispersed for the first time, matting powder is added and dispersed for the second time, ethyl acetate, n-butyl acetate, and propylene glycol methyl ether acetate are added and dispersed for the third time, and the viscosity is adjusted to obtain Component A; (2) preparing component B: mixing HDI curing agent and n-butyl acetate, heating and then keeping the temperature, cooling and discharging to obtain the component B; (3) Component A and component B are mixed to form a mixture.

8. The method for preparing a PU scratch-resistant self-repairing extra-matte transparent topcoat according to claim 7, characterized in that: The method further comprises the step (4) of mixing n-butyl acetate, propylene glycol methyl ether acetate and isopropyl alcohol and then mixing the mixture with the mixture in step (3).

9. The method for preparing a PU scratch-resistant self-repairing extra-matte transparent topcoat according to claim 7, characterized in that: In step (1), the rotation speed of the first dispersion and the third dispersion are both 600-800 r / min, and the dispersion time is 5-10 min. The rotation speed of the second dispersion is 1200-1500 r / min, and the dispersion time is 10-15 min.

10. The method for preparing a PU scratch-resistant self-repairing extra-matte transparent topcoat according to claim 7, characterized in that: In step (2), the temperature after heating is 60-80° C., and the insulation time is 20-50 minutes.

Images