A powder coating composition, its curing method and coating

Abstract

The present invention discloses a powder coating composition, its curing method and coating, which includes a textured low-temperature curing powder coating base powder composition and an effect pigment; wherein, the effect pigment is mixed with the textured low-temperature curing powder coating base powder composition through a thermal bonding process; the textured low-temperature curing powder coating base powder composition includes a polyester resin with an acid value of not less than 60 mgKOH / g, an epoxy resin with an epoxy equivalent of not less than 450 g / eq, and a texturing agent, and the texturing agent includes cellulose acetate; the viscosity of the polyester resin at 200 °C is not higher than 2500 mPa·s, and the viscosity of the epoxy resin at 150 °C is not higher than 4500 mPa·s; the present invention can obtain a cured coating with a special texture effect (similar to the hammered texture coating of the prior art), and this cured coating simultaneously has excellent scratch resistance, meeting the customized and diversified requirements of low-temperature curing application scenarios.

Description

Technical Field

[0001] The present invention belongs to the field of powder coatings, and particularly relates to a powder coating composition. The present invention also relates to a curing method of the powder coating composition and a coating applied thereby. Background Art

[0002] Thermosetting powder coatings are widely used to replace paints and waterborne paints to protect and decorate products in various fields due to their advantages such as environmental friendliness, low energy consumption, convenient construction, and no (or at least very little) VOC emissions.

[0003] In order to meet the diverse decorative effect requirements, textured powder coating products have been proposed. The textured powder coating products in the current technology are usually applied to metal substrates and need to be crosslinked and cured at a temperature of at least not lower than 180°C, and cannot be applied to application scenarios (such as heat-sensitive substrates) with low-temperature curing requirements (the curing conditions are usually not higher than 160°C, preferably not exceeding 140°C). As a result, the existing textured powder coating products cannot be used to obtain a textured effect cured coating in low-temperature curing application scenarios, and obviously they cannot meet the market's demands for customization and diversification.

[0004] Therefore, the applicant hopes to conduct research and development to solve the above technical problems. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a powder coating composition, a curing method thereof, and a coating, which can obtain a cured coating with a special textured effect (similar to the hammered effect coating in the prior art), and the cured coating has excellent scratch resistance at the same time, meeting the customization and diversification requirements of low-temperature curing application scenarios.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A powder coating composition includes a textured low-temperature curing powder coating base powder composition and an effect pigment; wherein,

[0008] The effect pigment is mixed with the textured low-temperature curing powder coating base powder composition by a thermal bonding process;

[0009] The textured low-temperature curing powder coating base powder composition includes a polyester resin with an acid value of not less than 60 mgKOH / g, an epoxy resin with an epoxy equivalent of not less than 450 g / eq, and a texturing agent;

[0010] The viscosity of the polyester resin at 200°C is not higher than 2500 mPa·s, and the viscosity of the epoxy resin at 150°C is not higher than 4500 mPa·s;

[0011] The texture agent includes cellulose acetate.

[0012] Preferably, the weight ratio of the texture agent in the texture-type low-temperature curing powder coating base powder composition is 0.01-0.2 wt%.

[0013] Preferably, the texture agent is cellulose acetate.

[0014] Preferably, the acid value range of the polyester resin is 70-90 mgKOH / g; and / or the viscosity range of the polyester resin at 200 °C is 200-2200 mPa·s; and / or the softening point temperature of the polyester resin is not higher than 120 °C; and / or the glass transition temperature of the polyester resin is not higher than 58 °C.

[0015] Preferably, the epoxy equivalent range of the epoxy resin is 500-650 g / eq; and / or the softening point temperature of the epoxy resin is not higher than 110 °C; and / or the viscosity range of the epoxy resin at 150 °C is 1000-4200 mPa·s.

[0016] Preferably, the weight ratio of the polyester resin to the epoxy resin is 1:4-4:1.

[0017] Preferably, the texture-type low-temperature curing powder coating base powder composition further includes a catalyst with a weight ratio of not less than 0.1 wt%, preferably ethyltriphenylphosphonium bromide.

[0018] Preferably, the weight ratio of the effect pigment in the texture-type low-temperature curing powder coating base powder composition is 0.5-5 wt%; and / or the effect pigment includes pearlescent pigment and / or aluminum powder and / or mica powder, and the effect pigment preferably uses aluminum powder.

[0019] Preferably, for a curing method of the powder coating composition as described above, the powder coating composition is cured by infrared heating, and the heating temperature is not higher than 150 °C and the heating time does not exceed 5 minutes.

[0020] Preferably, the heating temperature range is 130-140 °C, and / or the heating time range is 2-4 minutes;

[0021] A coating is obtained by spraying the powder coating composition as described above on a substrate and forming it through the curing method as described above.

[0022] Preferably, the substrate is a wood substrate.

[0023] It should be noted that the acid value detection standard involved in this application is based on ISO 3682-1998; the viscosity value detection standard is ASTM D 4287-1994, and the detection equipment used can be a standard commercial cone-plate viscometer (for example, using an ICI cone-plate viscometer (CONE&PLATE), with the model number being CAP 2000VISCOMETER from Brookfield); the detection standard for the epoxy equivalent involved is: GB / T 4612-2008; the detection standard for the softening point is: GB / T 4507-1999; the glass transition temperature data is obtained by detecting with a METTLER thermal analyzer of model DSC Q20, and the detection method uses differential scanning calorimetry (DSC, the full English name is: Differential Scanning Calorimetry), and its heating and temperature rising speed parameter is set at 20°C / minute.

[0024] It should be noted that the heating temperature involved in this application refers to the temperature setting for heating the substrate coated with the powder coating composition.

[0025] This application first designs a specific texture-type low-temperature curing powder coating base powder composition formula including at least a polyester resin with an acid value of not less than 60 mgKOH / g and a viscosity at 200°C of not higher than 2500 mPa·s, an epoxy resin with an epoxy equivalent of not less than 450 g / eq and a viscosity at 150°C of not higher than 4500 mPa·s, and a texturizer. The applicant surprisingly finds that by mixing an effect pigment with this specific texture-type low-temperature curing powder coating base powder composition through a thermal bonding process, a powder coating composition can be obtained, and a cured coating with a special texture effect (similar to the hammer texture effect coating in the prior art) can be obtained, and this cured coating simultaneously has excellent scratch resistance, meeting the customized and diversified requirements of low-temperature curing application scenarios. Description of the Drawings

[0026] Figure 1 It is a physical photo of the coating corresponding to Example 1. Detailed Description of the Invention

[0027] The embodiment of this application provides a powder coating composition, including a texture-type low-temperature curing powder coating base powder composition and an effect pigment; wherein, the effect pigment is mixed with the texture-type low-temperature curing powder coating base powder composition through a thermal bonding process; in this embodiment, any well-known thermal bonding (bonding) process can be adopted for the thermal bonding process, and this embodiment does not make special limitations on it; preferably, in the thermal bonding process, the thermal bonding temperature is recommended to be set at 50-55°C, and the thermal bonding time is recommended to be 2-5 minutes.

[0028] Preferably, in the present embodiment, the texture-type low-temperature curing powder coating base powder composition at least comprises the following raw materials:

[0029] A polyester resin with an acid value of not less than 60 mgKOH / g, and the viscosity of the polyester resin at 200 °C is not higher than 2500 mPa·s; in order to further facilitate the low-temperature curing effect and at the same time not affect the expected target texture effect, preferably, in the present embodiment, the acid value range of the polyester resin is 70-90 mgKOH / g, more preferably 75-85 mgKOH / g; and / or preferably, in the present embodiment, the viscosity range of the polyester resin at 200 °C is 200-2200 mPa·s, more preferably 500-2000 mPa·s; and / or preferably, in the present embodiment, the softening point temperature of the polyester resin is not higher than 120 °C, preferably 90-110 °C; and / or preferably, in the present embodiment, the glass transition temperature of the polyester resin is not higher than 58 °C, and the glass transition temperature is more preferably 45-55 °C; specifically preferably, the polyester resin can be Polyester ResinTM5013 from Zhejiang Transfar TianSong, with an acid value range of 75-85 mgKOH / g, a viscosity range at 200 °C of 500-2000 mPa·s, a softening point temperature range of 90-110 °C, and a glass transition temperature range of 51±3 °C. Of course, polyester resins with similar parameter ranges can also be used as preferred embodiments of the polyester resin used in this application;

[0030] An epoxy resin with an epoxy equivalent of not less than 450 g / eq, and the viscosity of the epoxy resin at 150 °C is not higher than 4500 mPa·s; in order to further facilitate the low-temperature curing effect and at the same time not affect the expected target texture effect, preferably, in the present embodiment, the epoxy equivalent range of the epoxy resin is 500-650 g / eq, more preferably 500-600 g / eq, and further preferably 500-560 g / eq; and / or preferably, in the present embodiment, the softening point temperature of the epoxy resin is not higher than 110 °C, more preferably 80-100 °C; and / or preferably, in the present embodiment, the viscosity range of the epoxy resin at 150 °C is 1000-4200 mPa·s, more preferably 2000-4200 mPa·s; specifically preferably, the epoxy resin can be EPOTEC YD 942 from epotec, with an epoxy equivalent range of 500-560 g / eq, a softening point temperature range of 80-95 °C, and a viscosity range at 150 °C of 1500-4000 mPa·s. Of course, epoxy resins with similar parameter ranges can also be used as preferred embodiments of the epoxy resin used in this application;

[0031] The texturing agent can specifically be a suitable texturing agent according to actual needs; preferably, in order to facilitate obtaining the desired hammered coating effect, in the present embodiment, the texturing agent includes cellulose acetate, specifically preferably, in the present embodiment, the texturing agent uses cellulose acetate; the applicant has tried other conventional texturing agents and found that the specific hammered coating effect cannot be achieved.

[0032] Preferably, in the present embodiment, the weight ratio of the polyester resin to the epoxy resin is 1:4 - 4:1, more preferably 1:2.5 - 2.5:1, and further preferably 1:1.5 - 1.5:1; preferably, in the present embodiment, the sum of the weight parts of the polyester resin and the epoxy resin accounts for 50 - 95 wt% of the weight of the base powder composition of the textured low-temperature curing powder coating, more preferably 60 - 85 wt%, and further preferably 65 - 80 wt%;

[0033] Preferably, in the present embodiment, the texturing agent accounts for 0.01 - 0.2 wt% of the weight of the base powder composition of the textured low-temperature curing powder coating, further preferably 0.02 - 0.1 wt%, and even more preferably 0.03 - 0.08 wt%; specifically preferably, it is recommended that the weight ratio of cellulose acetate in the base powder composition of the textured low-temperature curing powder coating should not be lower than 0.02 wt% nor higher than 0.4 wt%, otherwise it will significantly affect the expected hammered coating effect.

[0034] Preferably, in order to promote the crosslinking and curing reaction between the polyester resin and the epoxy resin, in the present embodiment, the base powder composition of the textured low-temperature curing powder coating further includes a catalyst accounting for not less than 0.1 wt% of its weight parts, more preferably including a catalyst accounting for 0.2 - 1 wt% of its weight parts, and further preferably 0.3 - 0.8 wt%; among them, the catalyst is preferably ethyltriphenylphosphonium bromide, and of course, catalysts with similar catalytic effects can also be used, and the present embodiment does not limit it uniquely.

[0035] Preferably, in the present embodiment, the effect pigment accounts for 0.5 - 5 wt% of the weight of the base powder composition of the textured low-temperature curing powder coating, more preferably 0.5 - 3 wt%, and even more preferably 0.8 - 2 wt%; and / or preferably, in the present embodiment, the effect pigment includes pearlescent pigment and / or aluminum powder and / or mica powder, more preferably, in order to facilitate obtaining the expected hammered coating effect, in the present embodiment, the effect pigment includes aluminum powder, further preferably, the effect pigment uses aluminum powder, and even more preferably floating aluminum powder, and the obtained target hammered effect is more stable and reliable.

[0036] All kinds of raw materials involved in the present application can be directly purchased in the market, and the sources of raw materials are easy to obtain.

[0037] In the specific implementation of the present application, leveling agents, degassing agents, antioxidants, dispersants, fillers, pigments, stabilizers, curing accelerators, functional additives or other additives known in the art can also be selected and added to the texture-type low-temperature curing powder coating base powder composition. These are all conventional technical choices for those skilled in the art. Specifically, the addition ratio of the filler and / or pigment can be conventionally selected according to actual needs, and the weight ratio can be preferably 0-40 wt% of the texture-type low-temperature curing powder coating base powder composition, more preferably 1-40 wt%. The filler and / or pigment can be selected, for example, from carbon black, aluminum hydroxide, barium sulfate, TiO2, etc.

[0038] When preparing the texture-type low-temperature curing powder coating base powder composition of the present application, any known preparation process can be used for preparation. Preferably, it is prepared by known processes such as mixing its raw materials, melt extrusion, and crushing. Of course, other known preparation processes can also be used to obtain the texture-type low-temperature curing powder coating base powder composition of this embodiment. The present application has no particular unique limitation on its preparation process.

[0039] To facilitate the low-temperature curing effect of the powder coating composition, preferably, this embodiment also proposes a curing method for the powder coating composition as described above. The powder coating composition is cured by infrared heating, the heating temperature is not higher than 150°C, and the heating time does not exceed 5 minutes. Preferably, in this embodiment, the heating temperature range is 130-140°C, and / or the heating time range is 2-4 minutes.

[0040] This embodiment also proposes a coating. The powder coating composition as described above is sprayed on a substrate and formed into a coating through the curing method as described above. Preferably, in this embodiment, the substrate is a wood substrate. In other embodiments, the substrate can also be other substrates with low-temperature curing requirements. Of course, the powder coating composition and its curing method provided in this embodiment can also be applied to conventional metal substrates. This embodiment does not make a unique limitation on this.

[0041] In this embodiment, the substrate can be pretreated and / or pre-sprayed. The coating thickness of this embodiment can be specifically selected according to actual needs. The recommended coating thickness range is 60-120 μm (the test standard is based on: ISO 2360-2017).

[0042] To verify the technical effects during the implementation of the present application, the present application specifically conducted the following multiple groups of examples as powder coating composition formula raw materials for specific test performance comparison:

[0043] Example 1: A powder coating composition comprising 98 wt% of a textured low-temperature curing powder coating base powder composition and 2 wt% of aluminum powder (grade ALUMINUM POWDER 2091 supplied by Benda-lutz, with an average particle size of 5 microns), the aluminum powder being mixed with the textured low-temperature curing powder coating base powder composition by a thermal bonding process, wherein, in the thermal bonding process, the thermal bonding temperature range is 50 - 55 °C and the thermal bonding time is 2 - 4 minutes.

[0044] In this Example 1, the formulation raw materials of the textured low-temperature curing powder coating base powder composition are prepared as shown in Table 1 below:

[0045] Table 1 Formulation table of the textured low-temperature curing powder coating base powder composition in this Example 1

[0046]

[0047] Example 2: The remaining technical solutions of this Example 2 are the same as those of Example 1, the difference being that, in this Example 2, the formulation raw materials of the textured low-temperature curing powder coating base powder composition are prepared as shown in Table 2 below:

[0048] Table 2 Formulation table of the textured low-temperature curing powder coating base powder composition in this Example 2

[0049]

[0050] Example 3: The remaining technical solutions of this Example 3 are the same as those of Example 1, the difference being that, in this Example 3, the formulation raw materials of the textured low-temperature curing powder coating base powder composition are prepared as shown in Table 3 below:

[0051] Table 3 Formulation table of the textured low-temperature curing powder coating base powder composition in this Example 3

[0052]

[0053] Example 4: The remaining technical solutions of this Example 4 are the same as those of Example 1, the difference being that, in this Example 4, the formulation raw materials of the textured low-temperature curing powder coating base powder composition are prepared as shown in Table 4 below:

[0054] Table 4 Formulation table of the textured low-temperature curing powder coating base powder composition in this Example 4

[0055]

[0056] Example 5: The remaining technical solutions of this Example 5 are the same as those of Example 1, the difference being that, in this Example 5, the formulation raw materials of the textured low-temperature curing powder coating base powder composition are prepared as shown in Table 5 below:

[0057] Table 5 Formulation Table of the Textured Low-Temperature Curing Powder Coating Base Powder Composition in Example 5

[0058]

[0059] Example 6: The remaining technical solutions of this Example 6 are the same as those of Example 1, except that in this Example 6, the formulation raw materials of the textured low-temperature curing powder coating base powder composition are prepared as shown in Table 6 below:

[0060] Table 6 Formulation Table of the Textured Low-Temperature Curing Powder Coating Base Powder Composition in Example 6

[0061]

[0062] Example 7: The remaining technical solutions of this Example 7 are the same as those of Example 1, except that in this Example 7, the formulation raw materials of the textured low-temperature curing powder coating base powder composition are prepared as shown in Table 7 below:

[0063] Table 7 Formulation Table of the Textured Low-Temperature Curing Powder Coating Base Powder Composition in Example 7

[0064]

[0065] Example 8: The remaining technical solutions of this Example 8 are the same as those of Example 1, except that in this Example 8, the powder coating composition comprises 97 wt% of the textured low-temperature curing powder coating base powder composition and 3 wt% of aluminum powder.

[0066] Example 9: The remaining technical solutions of this Example 9 are the same as those of Example 1, except that in this Example 9, the powder coating composition comprises 99 wt% of the textured low-temperature curing powder coating base powder composition and 1 wt% of aluminum powder.

[0067] Example 10: The remaining technical solutions of this Example 10 are the same as those of Example 1, except that in this Example 10, the powder coating composition comprises 99.5 wt% of the textured low-temperature curing powder coating base powder composition and 0.5 wt% of aluminum powder.

[0068] Example 11: The remaining technical solutions of this Example 11 are the same as those of Example 1, except that in this Example 11, the powder coating composition comprises 98 wt% of the textured low-temperature curing powder coating base powder composition and 2 wt% of pearlescent pigment (NB non-bonding pearlescent powder from Shanghai Jincheng).

[0069] Comparative Example 1: The remaining technical solutions of this Comparative Example 1 are the same as those of Example 1, except only that: in this Comparative Example 1, the Polyester Resin TM5013 polyester resin in Example 1 is replaced with that from allnex 4642 - 3, with a viscosity range of 1500 - 2300 mPa·s at 200 °C and an acid value range of 32 - 38 mg KOH / g.

[0070] Comparative Example 2: The rest of the technical solutions of this Comparative Example 2 are the same as those of Example 1, except that: in this Comparative Example 2, the Polyester Resin TM5013 polyester resin in Example 1 is replaced with SJ3B from Shenjian, with a viscosity range of 3500 - 5000 mPa·s at 200 °C and an acid value range of 68 - 75 mg KOH / g.

[0071] Comparative Example 3: The rest of the technical solutions of this Comparative Example 3 are the same as those of Example 1, except that: in this Comparative Example 3, the EPOTEC YD 942 from epotec epoxy resin in Example 1 is replaced with GMA1618 from Ningbo Nanhai Chemical, with an epoxy equivalent of 400 - 430 g / eq and a softening point temperature of 92 - 97 °C.

[0072] Comparative Example 4: The rest of the technical solutions of this Comparative Example 4 are the same as those of Example 1, except that: in this Comparative Example 4, a powder coating composition is provided, and the effect pigment is mixed with the texture - type low - temperature - curing powder coating base powder composition by a dry - blending process.

[0073] Comparative Example 5: The rest of the technical solutions of this Comparative Example 5 are the same as those of Example 1, except that: in this Comparative Example 5, the texture - type low - temperature - curing powder coating base powder composition in Example 1 is directly used as the powder coating composition.

[0074] The raw material formulations proposed in the above Examples 1 - 11 and Comparative Examples 1 - 5 of this application are respectively obtained corresponding base powder compositions through the same processes of weighing, premixing, melt - extrusion, grinding, cyclone separation, etc. (public - known process preparation techniques).

[0075] The powder coating compositions prepared by Examples 1 - 11 and Comparative Examples 1 - 5 are respectively used, and MDF of the same specification is selected as the substrate, and the infrared heating method is used to cure each powder coating composition. Among them, the heating temperature is 130 °C and the heating time is 3 minutes, and coatings are respectively obtained (for the coating photo obtained in Example 1, please refer to Figure 1 shown), and the performance test comparison results are as follows in Table 8:

[0076] Table 8 Performance Test Comparison of Each Group of Examples and Comparative Examples

[0077]

[0078] After comparative tests, it is found that the powder coating compositions provided in Examples 1-11 of the present embodiment have good substrate adhesion to the surface of the MDF substrate; at the same time, rapid curing under low-temperature conditions is achieved, which not only meets the basic performance of the powder coating for coating protection, but also effectively avoids the serious shrinkage holes of the coating film caused by the rapid evaporation of moisture in the MDF board and the problems of board deformation and cracking. More importantly, the expected target hammer-finish coating effect is obtained; further, in Examples 1-11 of the present application, Examples 1-10 have more obvious and excellent hammer-finish coating performance, indicating that when using aluminum powder as the effect pigment, it is more conducive to obtaining the target hammer-finish effect.

[0079] It should be specifically noted that the coating performance tests involved in this embodiment are carried out according to the test standards described in Table 9 below.

[0080] Table 9 Test Items and Test Standards

[0081] Test Items Implement Test Standards Coating Appearance By Visual Inspection Pencil Hardness GBT6739-1996 Cross-Cutting ISO 2409-2013 Impact ISO 6272-1-2011, 2-2011 Bending ISO 1519-2011 Cup Drawing ISO 1520-2006 MEK Test GB / T 23989-2009 Dry Heat BS EN 12722-2009 Damp Heat BS EN 12721-2009

[0082] It should be specifically noted that those skilled in the art can also apply the powder coating composition proposed in this application to the coating protection of other material substrates and obtain similar coating effects. This application will not be specifically described in detail.

[0083] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved.

[0084] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A powder coating composition, characterized in that, Comprising a textured low-temperature curable powder coating base powder composition and an effect pigment; wherein, The effect pigment is mixed with the textured low-temperature curable powder coating base powder composition by a thermal bonding process; The textured low-temperature curable powder coating base powder composition includes a polyester resin with an acid value of not less than 60 mgKOH / g, an epoxy resin, and a texturizing agent; The viscosity of the polyester resin at 200 °C is not higher than 2500 mPa·s, and the viscosity of the epoxy resin at 150 °C is not higher than 4500 mPa·s; the epoxy equivalent range of the epoxy resin is 500 - 650 g / eq; The texturizing agent includes cellulose acetate; The powder coating composition is suitable for curing the powder coating composition by infrared heating, with a heating temperature not higher than 150 °C and a heating time not exceeding 5 minutes.

2. The powder coating composition according to claim 1, characterized in that, The weight ratio of the texturizing agent in the textured low-temperature curable powder coating base powder composition is 0.01 - 0.2 wt%.

3. The powder coating composition according to claim 1, wherein The texturizing agent uses cellulose acetate.

4. The powder coating composition according to claim 1, characterized in that The acid value range of the polyester resin is 70 - 90 mgKOH / g; and / or the viscosity range of the polyester resin at 200 °C is 200 - 2200 mPa·s; and / or the softening point temperature of the polyester resin is not higher than 120 °C; and / or the glass transition temperature of the polyester resin is not higher than 58 °C.

5. The powder coating composition according to claim 1, characterized in that, The softening point temperature of the epoxy resin is not higher than 110 °C; and / or the viscosity range of the epoxy resin at 150 °C is 1000 - 4200 mPa·s.

6. The powder coating composition according to claim 1, wherein The weight ratio of the polyester resin to the epoxy resin is 1:4 - 4:

1.

7. The powder coating composition according to claim 1, characterized in that, The textured low-temperature curable powder coating base powder composition further includes a catalyst accounting for not less than 0.1 wt% of its weight.

8. The powder coating composition according to claim 7, characterized in that, The catalyst is ethyltriphenylphosphonium bromide.

9. The powder coating composition according to claim 1, characterized in that, The weight ratio of the effect pigment in the textured low-temperature curable powder coating base powder composition is 0.5 - 5 wt%; and / or the effect pigment includes pearlescent pigment and / or aluminum powder and / or mica powder.

10. The powder coating composition according to claim 9, characterized in that, The effect pigment uses aluminum powder.

11. A method for curing a powder coating composition according to any one of claims 1 to 10, characterized in that, Curing the powder coating composition by infrared heating, with a heating temperature not higher than 150 °C and a heating time not exceeding 5 minutes.

12. The curing method according to claim 11, characterized in that, The heating temperature range is 130 - 140 °C, and / or the heating time range is 2 - 4 minutes.

13. A coating, characterized in that, Spraying the powder coating composition according to any one of claims 1 - 10 on a substrate, and forming the coating by the curing method according to claim 11 or 12.

14. The coating according to claim 13, characterized in that, The substrate is a wood substrate.

Images