Metal effect powder coating composition and coating thereof

Abstract

The invention discloses a metal effect powder coating composition and a coating thereof. The metal effect powder coating composition comprises a powder coating base powder composition and a coated effect pigment, wherein the coated effect pigment accounts for 15 to 45 weight percent of the powder coating base powder composition, and more preferably, the coated effect pigment accounts for 20 to 40 weight percent of the powder coating base powder composition; the coated effect pigment comprises an effect pigment inner core, the effect pigment inner core is coated with a silicon layer, and the silicon layer is coated with a resin layer; the obtained coating has a unique metal flickering effect and is good in application stability.

Description

Technical Field

[0001] The invention belongs to the field of powder coatings, and in particular relates to a metal effect powder coating composition. The invention also relates to a metal effect coating prepared by using the metal effect powder coating composition. Background Art

[0002] Thermosetting powder coatings are widely used to replace paints and water-based paints to achieve protective decoration of products in various fields because of their advantages of being green, environmentally friendly, low energy consumption, easy to apply, and no (or at least very little) VOC emissions. In order to achieve more diverse decorative effects, the prior art has proposed to achieve this by adding effect pigments with various glittering effects. Not only is the application stability of the powder coatings poor, but the market also needs powder coating products with more diverse glittering effects.

[0003] Therefore, the applicant hopes to conduct research and development to solve the above technical problems. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a metallic effect powder coating composition and a coating thereof, wherein the obtained coating has a unique metallic glittering effect and good application stability.

[0005] The technical solution adopted by the present invention is as follows: A metallic effect powder coating composition comprises a powder coating base composition and a coated effect pigment; wherein the weight proportion of the coated effect pigment to the powder coating base composition is 15-45wt%, more preferably 20-40wt%; the coated effect pigment comprises an effect pigment core, wherein a silicon layer is coated on the effect pigment core, and the silicon layer is coated with a resin layer.

[0006] Preferably, the effect pigment core is made of aluminum powder.

[0007] Preferably, the D50 particle size of the coated effect pigment is in the range of 10-60 microns.

[0008] Preferably, the powder coating primer composition is transparent or at least translucent after being cured.

[0009] Preferably, the raw materials of the powder coating base powder composition include polyester resin and a curing agent for curing the polyester resin; the weight ratio of the polyester resin to the powder coating base powder composition is preferably not less than 55wt%, more preferably 65-95wt%, and further more preferably 70-92wt%; the weight ratio of the curing agent to the powder coating base powder composition is preferably in the range of 2-15wt%, more preferably 4-12wt%.

[0010] Preferably, the viscosity of the polyester resin at 200° C. is in the range of 1500-5000 mPa.s, and / or the acid value thereof is not higher than 45 mgKOH / g.

[0011] Preferably, the polyester resin has a viscosity at 200° C. in the range of 2500-4500 mPa.s, and / or an acid value in the range of 20-40 mgKOH / g.

[0012] Preferably, the resin layer comprises a thermoplastic resin, preferably consists of a thermoplastic resin.

[0013] Preferably, a metallic effect coating is obtained by spraying and curing the above-mentioned metallic effect powder coating composition on a substrate.

[0014] 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 involved is based on ASTM D 4287-1994, and the detection equipment used can be a standard commercial cone and plate viscometer (for example, ICI cone and plate viscometer (CONE&PLATE), brand CAP 2000 VISCOMETER from Brookfield); the D50 particle size data involved is obtained by particle size distribution test using laser diffraction (for example, Malvern Particle Size Analyzer 2000), and the test standard is based on ISO 13320-2009.

[0015] The present application proposes a specific coated effect pigment composed of an effect pigment core, a silicon layer and a resin layer, and then the specific coated effect pigment is mixed with a powder coating base powder composition to obtain a powder coating composition with a unique metallic glittering effect and good application stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG1 is a photo of a metallic effect coating corresponding to Example 16; FIG2 is a photo of the metal effect coating corresponding to Example 17; FIG3 is a photo of the metal effect coating corresponding to Example 18; FIG. 4 is a photograph of the metal effect coating corresponding to Example 19. DETAILED DESCRIPTION

[0017] The embodiment of the present application proposes a metallic effect powder coating composition, comprising a powder coating base composition and a coated effect pigment; wherein the weight proportion of the coated effect pigment to the powder coating base composition is 15-45wt%, more preferably 20-40wt%; the coated effect pigment comprises an effect pigment core, wherein a silicon layer is coated on the effect pigment core, and the silicon layer is coated with a resin layer.

[0018] Preferably, in this embodiment, the effect pigment core is aluminum powder. In other embodiments, other metal effect pigments can also be used as the core, such as pearl powder or mica powder. Preferably, in this embodiment, the D50 particle size of the coated effect pigment is in the range of 10-60 microns, more preferably 15-55 microns. Preferably, in order to further facilitate the application stability of the metal effect, in this embodiment, the resin layer includes a thermoplastic resin, preferably composed of a thermoplastic resin. Specifically preferably, in this embodiment, ZPBF- 318S (whose D50 particle size is 18 microns), ZPBF-3300S (whose D50 particle size is 39 microns) and ZPBF-5500S (whose D50 particle size is 54 microns) are used as the coated effect pigments in this embodiment. The structures of these coated effect pigments are all composed of "an effect pigment core, a silicon layer coated on the effect pigment core, and a resin layer coated on the silicon layer"; of course, in other implementations, other coated effect pigments with the same or similar structure can also be selected as the coated effect pigments in the embodiments of the present application, and this embodiment does not make the sole limitation thereto.

[0019] Preferably, in order to further facilitate obtaining a more excellent metallic effect, in the present embodiment, the powder coating base powder composition is transparent or at least translucent after curing; it should be noted that the transparency or translucent state involved in the present application means that the coating of the powder coating base powder composition after curing is at least translucent or partially translucent; further preferably, in order to further facilitate the light transmission effect of the coating, in the present embodiment, it is recommended not to add too much pigment / filler to the powder coating composition, wherein the weight proportion of pigment / filler to the powder coating composition is preferably not higher than 15wt%, more preferably not higher than 8wt%, further preferably not higher than 5wt%; or the weight proportion of pigment / filler to the powder coating composition is preferably not higher than 18wt%, more preferably not higher than 10wt%, further preferably not higher than 6wt%.

[0020] Preferably, in the present embodiment, the raw materials of the powder coating primer composition include polyester resin and a curing agent for curing the polyester resin; preferably, in the present embodiment, the weight proportion of the polyester resin in the powder coating primer composition is not less than 55wt%, more preferably 65-95wt%, and further more preferably 70-92wt%; preferably, in the present embodiment, the viscosity range of the polyester resin at 200°C is 1500-5000mPa.s, more preferably 2500-4500mPa.s; and / or preferably, in the present embodiment, the acid value of the polyester resin is not higher than 45 mgKOH / g, more preferably 20-40 mgKOH / g; specifically preferably, in the present embodiment, the polyester resin is FL-3011 provided by Yantai Fenglin New Materials, which has a viscosity range of 2800-4100mPa.s at 200°C and an acid value range of 30-36 mgKOH / g.

[0021] Preferably, in this embodiment, the weight ratio of the curing agent to the powder coating base powder composition is preferably in the range of 2-15wt%, more preferably 4-12wt%; preferably, in this embodiment, the curing agent includes TGIC (triglycidyl isocyanurate) and / or hydroxyalkylamide; further preferably, in this embodiment, the curing agent is TGIC and / or hydroxyalkylamide.

[0022] All kinds of raw materials involved in this application can be directly purchased on the market, and the sources of raw materials are easy to obtain.

[0023] In the specific implementation of the present application, known leveling agents, degassing agents, antioxidants, dispersants, fillers, pigments, stabilizers, curing accelerators, functional additives and / or other additives may also be added to the powder coating base powder composition. These are conventional technical choices of those skilled in the art; specifically, fillers and / or pigments may be, for example, carbon black, aluminum hydroxide, barium sulfate, TiO2, etc.

[0024] When preparing the powder coating base powder composition of the present application, any known preparation process can be used for preparation; preferably, in this embodiment, the powder coating base powder composition is obtained by mixing, melt extrusion, and crushing. Of course, other known preparation processes can also be used to obtain the powder coating base powder composition of this embodiment, and the present application has no particular limitation on its preparation process.

[0025] Preferably, in this embodiment, the coated effect pigment is bonded to the coating base powder composition by a thermal bonding process; as an optional preparation method (but not recommended by the applicant), the powder coating base powder composition and the coated effect pigment are mixed simultaneously to obtain a powder coating composition with a metallic effect (but its metallic effect and application stability will be deteriorated).

[0026] Preferably, in this embodiment, the thermal bonding process can adopt any known thermal bonding (bonding) process, and this embodiment does not specifically limit it; preferably, in the thermal bonding process, the thermal bonding temperature is recommended to be set at 50-60°C, more preferably 50-55°C, and the thermal bonding time is recommended to be selected at 2-5 minutes.

[0027] Preferably, this embodiment provides a metallic effect coating, which is obtained by spraying and curing the powder coating composition with metallic effect as described above on a substrate.

[0028] In order to verify the technical effect of the present application, the present application specifically conducted the following multiple groups of examples as raw materials for powder coating composition formulations for specific test performance comparison: Example 1: A powder coating composition with a metallic effect, comprising 75 wt% of a powder coating base composition and 25 wt% of an encapsulated effect pigment (brand name ZPBF-318S from Changsha Zuxing New Materials Co., Ltd.); the encapsulated effect pigment is compounded with the powder coating base composition by a thermal bonding process, wherein in the thermal bonding process, the thermal bonding temperature range is 51° C., and the thermal bonding time is 2.5 minutes; In this embodiment 1, the powder coating primer composition is prepared according to the formula raw materials shown in Table 1 below:

[0029] Example 2: The rest of the technical scheme of Example 2 is the same as that of Example 1, except that, in Example 2, the polyester resin brand in Example 1 is replaced by GH-3331 provided by Zhejiang Guanghua, which has a viscosity range of 2500-3500 mPa.s at 200°C and an acid value range of 32-37 mgKOH / g.

[0030] Example 3: The remaining technical solutions of Example 3 are the same as those of Example 1, except that in Example 3, the polyester resin grade in Example 1 is replaced by CRYLCOAT ® 4642-3 polyester resin, its viscosity at 200°C ranges from 1500-2300 mPa.s, and its acid value ranges from 32-38 mgKOH / g.

[0031] Example 4: The rest of the technical solutions of Example 4 are the same as those of Example 1, except that, in Example 4, the polyester resin brand in Example 1 is replaced by GH-3337 polyester resin provided by Zhejiang Guanghua, which has a viscosity range of 4300-5500 mPa.s at 200°C and an acid value range of 50-56 mg KOH / g.

[0032] Example 5: The rest of the technical solutions of Example 5 are the same as those of Example 1, except that, in Example 5, the polyester resin brand in Example 1 is replaced by Excalibur's SJ3B, which has a viscosity range of 3500-5000 mPa.s at 200°C and an acid value range of 68-75 mgKOH / g.

[0033] Embodiment 6: The remaining technical solutions of Embodiment 6 are the same as those of Embodiment 1, except that, in Embodiment 6, the powder coating primer composition is prepared according to the formula raw materials shown in Table 2 below:

[0034] Embodiment 7: The remaining technical solutions of Embodiment 7 are the same as those of Embodiment 1, except that, in Embodiment 7, the powder coating primer composition is prepared according to the formula raw materials shown in Table 3 below:

[0035] Example 8: The rest of the technical solutions of Example 8 are the same as those of Example 1, except that Example 8 provides a powder coating composition with a metallic effect, comprising 70 wt % of a powder coating base composition and 30 wt % of an encapsulated effect pigment (brand ZPBF-318S from Changsha Zuxing New Materials Co., Ltd.).

[0036] Example 9: The rest of the technical solutions of Example 9 are the same as those of Example 1, except that Example 9 provides a powder coating composition with a metallic effect, comprising 65 wt % of a powder coating base composition and 35 wt % of an encapsulated effect pigment (brand ZPBF-318S from Changsha Zuxing New Materials Co., Ltd.).

[0037] Example 10: The rest of the technical solutions of Example 10 are the same as those of Example 1, except that Example 10 provides a powder coating composition with a metallic effect, comprising 60 wt % of a powder coating base composition and 40 wt % of an encapsulated effect pigment (brand ZPBF-318S from Changsha Zuxing New Materials Co., Ltd.).

[0038] Example 11: The rest of the technical solutions of Example 11 are the same as those of Example 1, except that Example 11 provides a powder coating composition with a metallic effect, comprising 55 wt % of a powder coating base composition and 45 wt % of an encapsulated effect pigment (brand ZPBF-318S from Changsha Zuxing New Materials Co., Ltd.).

[0039] Example 12: The rest of the technical solutions of Example 12 are the same as those of Example 1, except that Example 12 provides a powder coating composition with a metallic effect, comprising 80 wt % of a powder coating base composition and 20 wt % of an encapsulated effect pigment (brand ZPBF-318S from Changsha Zuxing New Materials Co., Ltd.).

[0040] Example 13: The rest of the technical solutions of Example 13 are the same as those of Example 1, except that Example 13 provides a powder coating composition with a metallic effect, comprising 85 wt % of a powder coating base composition and 15 wt % of an encapsulated effect pigment (brand ZPBF-318S from Changsha Zuxing New Materials Co., Ltd.).

[0041] Example 14: The rest of the technical solutions of Example 14 are the same as those of Example 1, except that, in Example 14, the brand of the coated effect pigment in Example 1 is replaced by ZPBF-3300S.

[0042] Example 15: The rest of the technical solutions of Example 15 are the same as those of Example 1, except that, in Example 15, the brand of the coated effect pigment in Example 1 is replaced by ZPBF-3300S.

[0043] Example 16: The remaining technical solutions of Example 16 are the same as those of Example 1, except that, in Example 16, the powder coating primer composition in Example 1 is replaced with TIGER Drylac produced by Tiger Surface Technology New Materials (Suzhou) Co., Ltd. ® 049 / 93765 is a transparent powder, and the polyester resin used is the same as that in Example 1.

[0044] Example 17: The remaining technical solutions of Example 17 are the same as those of Example 1, except that, in Example 17, the powder coating primer composition in Example 1 is replaced with TIGER Drylac produced by Tiger Surface Technology New Materials (Suzhou) Co., Ltd. ® 049 / 93860 is a transparent powder, and the polyester resin used is the same as that in Example 1.

[0045] Example 18: The remaining technical solutions of Example 18 are the same as those of Example 1, except that, in Example 18, the powder coating primer composition in Example 1 is replaced with TIGER Drylac produced by Tiger Surface Technology New Materials (Suzhou) Co., Ltd. ® 049 / 93893 is a transparent powder, and the polyester resin used is the same as that in Example 1.

[0046] Example 19: The remaining technical solutions of Example 19 are the same as those of Example 1, except that, in Example 19, the powder coating primer composition in Example 1 is replaced with TIGER Drylac produced by Tiger Surface Technology New Materials (Suzhou) Co., Ltd. ® 049 / 93861 is a transparent powder, and the polyester resin used is the same as that in Example 1.

[0047] Comparative Example 1: The rest of the technical solutions of Comparative Example 1 are the same as those of Example 1, except that Comparative Example 1 provides a powder coating composition with a metallic effect, comprising 88 wt % of a powder coating base composition and 12 wt % of an encapsulated effect pigment (brand name ZPBF-318S from Changsha Zuxing New Materials Co., Ltd.).

[0048] Comparative Example 2: The rest of the technical scheme of Comparative Example 2 is the same as that of Example 1, except that, in Comparative Example 2, the coated effect pigment in Example 1 is replaced by a leafing aluminum pigment, the brand of which is ALUMINUM POWDER 2091 provided by Benda-lutz, and the average particle size of which is 5 μm.

[0049] Comparative Example 3: The rest of the technical solutions of Comparative Example 3 are the same as those of Example 1, except that, in Comparative Example 3, the encapsulated effect pigment in Example 1 is replaced with NB free-bonding pearlescent powder PMW04101NB produced by Shanghai Jincheng.

[0050] Comparative Example 4: The rest of the technical scheme of Comparative Example 4 is the same as that of Example 1, except that, in this Comparative Example 4, the coated effect pigment in Example 1 is replaced with the following structure: It comprises an effect pigment core, on which a resin layer is directly coated (omitting the silicon layer in the middle).

[0051] Comparative Example 5: The rest of the technical scheme of Comparative Example 5 is the same as that of Example 1, except that, in this Comparative Example 5, the coated effect pigment in Example 1 is replaced with the following structure: The invention comprises an effect pigment core, which is covered with a silicon layer and no longer covered with a resin layer.

[0052] The present application obtains the corresponding powder coating primer compositions according to the implementation schemes proposed in the above Examples 1-19 and Comparative Examples 1-5.

[0053] The powder coating compositions prepared in Examples 1-19 and Comparative Examples 1-5 were respectively used, and the same aluminum plate was selected as the substrate. Each powder coating composition was cured by baking heating, wherein the heating temperature was 200° C. and the heating time was 15 minutes, and coatings were obtained respectively (the coating obtained in Example 16 is shown in FIG. Figure 1As shown; the coating photo obtained in Example 17 can be found in Figure 2 As shown; the coating photo obtained in Example 18 can be found in Figure 3 As shown; the coating photo obtained in Example 19 can be found in Figure 4 The performance test comparison results are shown in Table 4:

[0054] After comparative testing, it was found that the powder coating compositions provided in Examples 1-3, 7-12, and 14-19 have a significantly outstanding metallic effect and good application stability.

[0055] It should be noted that the coating performance test involved in this embodiment is carried out according to the test standard described in Table 5 below.

[0056]

[0057] It should be 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 to obtain similar coating effects, which will not be described in detail in this application.

[0058] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0059] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A metallic effect powder coating composition, characterized in that: It comprises a powder coating base powder composition and a coated effect pigment; wherein the weight proportion of the coated effect pigment to the powder coating base powder composition is 15-45wt%, more preferably 20-40wt%; the coated effect pigment comprises an effect pigment core, wherein a silicon layer is coated on the effect pigment core, and the silicon layer is coated with a resin layer.

2. The metallic effect powder coating composition according to claim 1, characterized in that: The effect pigment core is made of aluminum powder.

3. The metallic effect powder coating composition according to claim 1, characterized in that: The D50 particle size of the coated effect pigment is in the range of 10-60 microns.

4. The metallic effect powder coating composition according to claim 1, characterized in that: The powder coating primer composition is transparent or at least translucent after being cured.

5. The metallic effect powder coating composition according to claim 1 or 4, characterized in that: The raw materials of the powder coating primer composition include polyester resin and a curing agent for curing the polyester resin; the weight ratio of the polyester resin to the powder coating primer composition is preferably not less than 55wt%, more preferably 65-95wt%, and further more preferably 70-92wt%; the weight ratio of the curing agent to the powder coating primer composition is preferably in the range of 2-15wt%, and more preferably 4-12wt%.

6. The metallic effect powder coating composition according to claim 5, characterized in that: The viscosity of the polyester resin at 200° C. is in the range of 1500-5000 mPa.s, and / or the acid value thereof is not higher than 45 mgKOH / g.

7. The metallic effect powder coating composition according to claim 6, characterized in that: The polyester resin has a viscosity at 200° C. in the range of 2500-4500 mPa.s, and / or an acid value in the range of 20-40 mgKOH / g.

8. The metallic effect powder coating composition according to claim 1, characterized in that: The resin layer includes a thermoplastic resin, and preferably consists of a thermoplastic resin.

9. A metallic effect coating, characterized in that: The powder coating composition having a metallic effect as claimed in any one of claims 1 to 8 is sprayed on a substrate and cured to obtain the powder coating composition.

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