Molybdate pigment as well as preparation method and application thereof

Abstract

The invention discloses a molybdate pigment as well as a preparation method and application thereof. The molybdate pigment comprises erbium-doped neodymium molybdate, and the preparation method comprises the following steps: mixing neodymium oxide, erbium oxide and molybdenum trioxide, carrying out wet ball milling, drying, calcining and grinding. The molybdate pigment has the advantages of high near-infrared reflectivity, remarkable light environment induced discoloration effect, safety, environment friendliness and the like, can be applied to the fields of building decoration, energy-saving materials and the like, and is simple in preparation method, high in production efficiency, low in production cost and suitable for large-scale industrial production and application.

Description

Technical Field

[0001] The invention relates to the technical field of inorganic pigments, and in particular to a molybdate pigment and a preparation method and application thereof. Background Art

[0002] Inorganic pigments have the advantages of relatively stable color, good fire retardant effect, strong chemical corrosion resistance, etc. They are widely used in architectural decoration, ceramics, glass and other fields. However, most of the traditional inorganic pigments have relatively single functions, which limits their further expansion of application. Studies have shown that by introducing rare earth elements and other methods, inorganic pigments can be given some functional effects (such as luminescence, near-infrared reflection, color change, etc.), thereby further expanding the application range of inorganic pigments. For example, color-changing pigments with light environment-induced color change effects can show obvious color changes under different light sources and have unique decorative effects; near-infrared reflective pigments can selectively reflect near-infrared radiation in sunlight, which has the effect of reducing the surface temperature of objects and has important application value in the field of building energy conservation.

[0003] Green pigments are widely used in our daily life, but the near-infrared reflectivity of existing green high near-infrared reflective pigments can only reach 30% to 70%, and the near-infrared reflectivity performance needs to be further improved. In addition, these pigments usually contain harmful elements such as cobalt and chromium, which are not conducive to environmental protection, resulting in difficulty and high cost in the later recycling of pigments, making it difficult to fully meet the growing practical application requirements.

[0004] Therefore, it is of great significance to develop a green inorganic pigment with high near-infrared reflectivity, significant light environment-induced color change effect, and safety and environmental protection. Summary of the invention

[0005] The purpose of the present invention is to provide a molybdate colorant and a preparation method and application thereof.

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

[0007] A molybdate pigment, comprising erbium-doped neodymium molybdate (chemical formula: (Nd 1-x Er x ) 6 MoO 12 ).

[0008] Preferably, the molar ratio of the neodymium element to the erbium element in the erbium-doped neodymium molybdate is 0.25 to 9:1.

[0009] Further preferably, the molar ratio of the neodymium element to the erbium element in the erbium-doped neodymium molybdate is 0.25 to 4:1.

[0010] Preferably, the ratio of the total molar amount of neodymium and erbium elements in the erbium-doped neodymium molybdate to the molar amount of molybdenum element is 5.5 to 6.5:1.

[0011] Preferably, the main crystal phase of the erbium-doped neodymium molybdate is rhombohedral phase or cubic phase.

[0012] A preparation method of the molybdate pigment as described above includes the following steps: mixing neodymium oxide, erbium oxide and molybdenum trioxide for wet ball milling, and then drying, calcining and grinding to obtain the molybdate pigment.

[0013] Preferably, the drying is carried out at a temperature of 60°C to 100°C, and the drying time is 10h to 20h.

[0014] Preferably, the calcining is carried out at a temperature of 1100°C to 1500°C, and the heat preservation time is 1h to 9h.

[0015] Preferably, the calcining includes the following process: first controlling the heating rate to be 2.5°C / min to 10°C / min and heating from room temperature to 1100°C to 1500°C, then heat preserving for 1h to 9h, then controlling the cooling rate to be 5°C / min to 10°C / min and cooling to 550°C to 650°C, and then naturally cooling to room temperature.

[0016] An architectural decoration material, which contains the above-mentioned molybdate pigment.

[0017] An energy-saving material, which contains the above-mentioned molybdate pigment.

[0018] The beneficial effects of the present invention are as follows: The molybdate pigment of the present invention has the advantages of high near-infrared reflectivity, significant light environment-induced color change effect, safety and environmental protection, etc. It can be used in the fields of architectural decoration, energy-saving materials, etc., and its preparation method is simple, the production efficiency is high, and the production cost is low, which is suitable for large-scale industrial production and application.

[0019] Specifically:

[0020] 1) The molybdate pigment of the present invention has a high near-infrared reflectivity (greater than 81%) and a significant light environment-induced color change effect (green under sunlight and brown under standard light source A, with obvious color change effect). While endowing the product with a unique decorative effect, it can also improve the heat insulation performance of the product, and the application range is wider;

[0021] 2) The molybdate pigment of the present invention does not contain harmful elements such as cobalt and chromium, the raw materials are safe and environmentally friendly, the potential harm to the human body and the environment during the preparation and use process is small, and the difficulty and cost of the later recycling treatment of the pigment are small.

[0022] 3) The preparation process flow of the molybdate pigment of the present invention is simple, easy for large-scale industrial production, with high production efficiency and low production cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is the XRD pattern of the molybdate pigment in Example 1.

[0024] Figure 2 It is the near-infrared reflection spectrum diagram of the molybdate pigment in Example 1.

[0025] Figure 3 It is the appearance diagram of the molybdate pigments in Examples 1-5 under standard light source D65 and standard light source A.

[0026] Figure 4 It is the thermal infrared diagram of the aluminum plate coated with the molybdate pigments in Examples 1-5 after being irradiated by an infrared lamp for 10 minutes. DETAILED DESCRIPTION OF THE INVENTION

[0027] The present invention will be further explained and described below in conjunction with specific embodiments.

[0028] Example 1:

[0029] A molybdate pigment, and its preparation method is as follows:

[0030] 61.5 g of neodymium oxide (Nd 2 O 3 ), 17.5 g of erbium oxide (Er 2 O 3 ), and 11.0 g of molybdenum trioxide (MoO 3 ) are added to 100 mL of absolute ethanol and ground evenly, then placed in a blast drying oven at 80 °C for 12 h, then placed in a muffle furnace. First, control the heating rate to rise from room temperature to 1000 °C at 5 °C / min, then control the heating rate to continue rising to 1300 °C at 2.5 °C / min, then keep warm for 3 h, then control the cooling rate to cool to 600 °C at 5 °C / min, then naturally cool to room temperature, and then grind to obtain the molybdate pigment.

[0031] Performance test:

[0032] 1) The X-ray diffraction (XRD) pattern of the molybdate pigment in this example is as Figure 1 shown.

[0033] It can be Figure 1 seen from: The main crystal phase is neodymium erbium molybdate (Nd 1-x Er x ) 6 MoO 12 with a space group of R.

[0034] 2) The near-infrared reflection spectrogram of the molybdate pigment in this embodiment is as Figure 2 shown.

[0035] It can be seen from Figure 2 that: the near-infrared reflectivity of the molybdate pigment is 85.6%, and the near-infrared reflectivity is high.

[0036] 3) The appearance diagrams of the molybdate pigment in this embodiment under standard light source D65 and standard light source A are as Figure 3 shown.

[0037] It can be seen from Figure 3 that: the molybdate pigment appears green under standard light source D65 and brown under standard light source A, and the light environment-induced color change effect is significant.

[0038] 4) The molybdate pigment in this embodiment is dispersed in absolute ethanol to form a slurry, and then the slurry is coated on the surface of the aluminum plate and dried. Then, it is vertically irradiated with an infrared lamp (preheated to a stable power) at a height of 0.5 m from the surface of the aluminum plate for 10 minutes. Then, an infrared thermal imager is used to record the temperature and the thermal infrared diagram. The obtained thermal infrared diagram of the aluminum plate is as Figure 4 (The aluminum plate without coated molybdate pigment is used as a blank control) shown.

[0039] It can be seen from Figure 4 that: the temperature of the aluminum plate coated with the molybdate pigment is 12.8 °C lower than that of the blank aluminum plate, indicating that the molybdate pigment can indeed improve the heat insulation performance of the product.

[0040] Example 2:

[0041] A molybdate pigment, and its preparation method is as follows:

[0042] 45.1 g of neodymium oxide, 34.2 g of erbium oxide and 10.8 g of molybdenum trioxide are added to 100 mL of absolute ethanol and ground evenly. Then, it is placed in a blast drying oven and dried at 80 °C for 12 h. Then, it is placed in a muffle furnace. First, the heating rate is controlled at 5 °C / min and heated from room temperature to 1000 °C. Then, the heating rate is controlled at 2.5 °C / min and continued to be heated to 1300 °C. Then, it is kept warm for 3 h. Then, the cooling rate is controlled at 5 °C / min and cooled to 600 °C. Then, it is naturally cooled to room temperature and ground to obtain the molybdate pigment.

[0043] Performance test:

[0044] 1) The XRD diagram of the molybdate pigment in this embodiment is similar to that of the molybdate pigment in Example 1.

[0045] 2) The near-infrared reflectivity of the molybdate pigment in this embodiment is 81.8%, and the near-infrared reflectivity is high.

[0046] 3) The appearance diagrams of the molybdate pigment in this embodiment under the standard light source D65 and the standard light source A are as Figure 3 shown.

[0047] It can be seen from Figure 3 that: the molybdate pigment appears green under the standard light source D65 and brown under the standard light source A, and the photoenvironment-induced color change effect is significant.

[0048] 4) The molybdate pigment in this embodiment is dispersed in absolute ethanol to form a slurry, and then the slurry is coated on the surface of the aluminum plate and dried. Then, it is vertically irradiated with an infrared lamp (preheated to a stable power) at a height of 0.5 m from the surface of the aluminum plate for 10 min, and then an infrared thermal imager is used to record the temperature and the thermal infrared image. The obtained thermal infrared image of the aluminum plate is as Figure 4 (The aluminum plate without coated molybdate pigment is used as a blank control) shown.

[0049] It can be seen from Figure 4 that: the temperature of the aluminum plate coated with the molybdate pigment is 6.6 °C lower than that of the blank aluminum plate, indicating that the molybdate pigment can indeed improve the heat insulation performance of the product.

[0050] Example 3:

[0051] A molybdate pigment, and its preparation method is as follows:

[0052] 29.6 g of neodymium oxide, 50.2 g of erbium oxide and 10.5 g of molybdenum trioxide are added to 100 mL of absolute ethanol and ground evenly. Then, it is placed in a blast drying oven and dried at 80 °C for 12 h. Then, it is placed in a muffle furnace. First, the heating rate is controlled at 5 °C / min and heated from room temperature to 1000 °C, and then the heating rate is controlled at 2.5 °C / min and continued to be heated to 1300 °C. Then, it is kept warm for 3 h, and then the cooling rate is controlled at 5 °C / min and cooled to 600 °C, and then naturally cooled to room temperature. Then, it is ground to obtain the molybdate pigment.

[0053] Performance test:

[0054] 1) The XRD diagram of the molybdate pigment in this embodiment is similar to that of the molybdate pigment in Example 1.

[0055] 2) The near-infrared reflectivity of the molybdate pigment in this embodiment is 82.6%, and the near-infrared reflectivity is high.

[0056] 3) The appearance diagrams of the molybdate pigment in this embodiment under the standard light source D65 and the standard light source A are as Figure 3 shown.

[0057] It can be seen from Figure 3 that: the molybdate pigment appears green under the standard light source D65 and brown under the standard light source A, and the photoenvironment-induced color change effect is significant.

[0058] 4) Disperse the molybdate pigment in this example with absolute ethanol to make a slurry, then coat the slurry on the surface of the aluminum plate and dry it. Then, use an infrared lamp (preheated to a stable power) to vertically irradiate it at a height of 0.5 m from the surface of the aluminum plate for 10 minutes, and then use an infrared thermal imager to record the temperature and thermal infrared image. The thermal infrared image of the obtained aluminum plate is as Figure 4 (The aluminum plate without coated molybdate pigment is used as a blank control) shown.

[0059] It can be seen from Figure 4 that: The temperature of the aluminum plate coated with molybdate pigment is 7.8 °C lower than that of the blank aluminum plate, indicating that the molybdate pigment can indeed improve the heat insulation performance of the product.

[0060] Example 4:

[0061] A kind of molybdate pigment, and its preparation method is as follows:

[0062] Add 61.5 g of neodymium oxide, 17.5 g of erbium oxide and 11.0 g of molybdenum trioxide into 100 mL of absolute ethanol, grind them evenly, then place them in a blast drying oven at 80 °C for 12 h, and then place them in a muffle furnace. First, control the heating rate to be 5 °C / min and heat from room temperature to 1000 °C, then control the heating rate to be 2.5 °C / min and continue to heat to 1200 °C, then keep warm for 3 h, then control the cooling rate to be 5 °C / min and cool to 600 °C, and then naturally cool to room temperature, and then grind it to obtain the molybdate pigment.

[0063] Performance test:

[0064] 1) The XRD pattern of the molybdate pigment in this example is similar to that of the molybdate pigment in Example 1.

[0065] 2) The near-infrared reflectivity of the molybdate pigment in this example is 88.0%, and the near-infrared reflectivity is high.

[0066] 3) The appearance diagrams of the molybdate pigment in this example under standard light source D65 and standard light source A are as Figure 3 shown.

[0067] It can be seen from Figure 3 that: The molybdate pigment is green under standard light source D65 and brown under standard light source A, and the photoenvironment-induced color change effect is significant.

[0068] 4) Disperse the molybdate pigment in this example with absolute ethanol to make a slurry, then coat the slurry on the surface of the aluminum plate and dry it. Then, use an infrared lamp (preheated to a stable power) to vertically irradiate it at a height of 0.5 m from the surface of the aluminum plate for 10 minutes, and then use an infrared thermal imager to record the temperature and thermal infrared image. The thermal infrared image of the obtained aluminum plate is as Figure 4As shown in (the aluminum plate without coated molybdate pigment was used as a blank control).

[0069] It can be seen from (that) Figure 4 that the temperature of the aluminum plate coated with molybdate pigment is 13.8 °C lower than that of the blank aluminum plate, indicating that the molybdate pigment can indeed improve the heat insulation performance of the product.

[0070] Example 5:

[0071] A kind of molybdate pigment, and its preparation method is as follows:

[0072] 61.5 g of neodymium oxide, 17.5 g of erbium oxide and 11.0 g of molybdenum trioxide were added to 100 mL of absolute ethanol and ground evenly, then placed in a blast drying oven at 80 °C for 12 h, and then placed in a muffle furnace. First, the heating rate was controlled at 5 °C / min and heated from room temperature to 1000 °C, then the heating rate was controlled at 2.5 °C / min and continued to heat to 1100 °C, then kept warm for 3 h, then the cooling rate was controlled at 5 °C / min and cooled to 600 °C, and then naturally cooled to room temperature, and then ground to obtain the molybdate pigment.

[0073] Performance test:

[0074] 1) The XRD pattern of the molybdate pigment in this example is similar to that of the molybdate pigment in Example 1.

[0075] 2) The near-infrared reflectivity of the molybdate pigment in this example is 90.1%, and the near-infrared reflectivity is high.

[0076] 3) The appearance diagrams of the molybdate pigment in this example under standard light source D65 and standard light source A are as Figure 3 shown.

[0077] It can be seen from (that) Figure 3 the molybdate pigment is green under standard light source D65 and brown under standard light source A, and the photoenvironment-induced color change effect is significant.

[0078] 4) The molybdate pigment in this example was dispersed in absolute ethanol to make a slurry, then the slurry was coated on the surface of the aluminum plate and dried, and then irradiated vertically at a height of 0.5 m from the surface of the aluminum plate with an infrared lamp (preheated to a stable power) for 10 min, and then an infrared thermal imager was used to record the temperature and thermal infrared image. The obtained thermal infrared image of the aluminum plate is as Figure 4 (the aluminum plate without coated molybdate pigment was used as a blank control) shown.

[0079] It can be seen from (that) Figure 4 the temperature of the aluminum plate coated with molybdate pigment is 17.8 °C lower than that of the blank aluminum plate, indicating that the molybdate pigment can indeed improve the heat insulation performance of the product.

[0080] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. A molybdate colorant, characterized in that: The composition includes erbium-doped neodymium molybdate.

2. The molybdate colorant according to claim 1, characterized in that: The molar ratio of the neodymium element to the erbium element in the erbium-doped neodymium molybdate is 0.25-9:

1.

3. The molybdate colorant according to claim 1 or 2, characterized in that: The ratio of the total molar amount of the neodymium element and the erbium element in the erbium-doped neodymium molybdate to the molar amount of the molybdenum element is 5.5-6.5:

1.

4. The molybdate colorant according to claim 1 or 2, characterized in that: The main crystal phase of the erbium-doped neodymium molybdate is a rhombohedral phase or a cubic phase.

5. A method for preparing the molybdate colorant according to any one of claims 1 to 4, characterized in that: The method comprises the following steps: mixing neodymium oxide, erbium oxide and molybdenum trioxide, performing wet ball milling, and then drying, calcining and grinding to obtain molybdate colorant.

6. The preparation method according to claim 5, characterized in that: The drying is carried out at a temperature of 60° C. to 100° C., and the drying time is 10 h to 20 h.

7. The preparation method according to claim 5 or 6, characterized in that: The calcination is carried out at a temperature of 1100° C. to 1500° C., and the heat preservation time is 1 hour to 9 hours.

8. The preparation method according to claim 5 or 6, characterized in that: The calcination process includes the following steps: firstly controlling the heating rate to be 2.5°C / min-10°C / min to heat from room temperature to 1100°C-1500°C, then keeping the temperature for 1h-9h, then controlling the cooling rate to be 5°C / min-10°C / min to cool to 550°C-650°C, and then naturally cooling to room temperature.

9. A building decoration material, characterized in that: The molybdate colorant comprises the molybdate colorant according to any one of claims 1 to 4.

10. An energy-saving material, characterized in that: The molybdate colorant comprises the molybdate colorant according to any one of claims 1 to 4.

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