Titanium-niobium oxide coating material, preparation method and application thereof

Abstract

This invention provides a titanium niobium oxide coating material, its preparation method, and its application. The preparation method includes the following steps: mixing titanium pentoxide, niobium pentoxide, a binder, a thickener, and a solvent to obtain a slurry; spray granulating the slurry to obtain powder with a particle size D50 of less than 45 μm; after debinding, the obtained powder is cold isostatically pressed into a green body, which is then crushed to obtain crushed particles; the crushed particles are then pressureless sintered to obtain the titanium niobium oxide coating material. The preparation method provided by this invention can obtain a titanium niobium oxide coating material with high purity, high density, uniform particle size, and high yield.

Description

Technical Field

[0001] This invention belongs to the field of optical coating technology, and relates to a coating material, its preparation method and application, and particularly to a titanium niobium oxide coating material, its preparation method and application. Background Technology

[0002] Titanium niobium oxide evaporators are mainly used in the optical coating industry due to their stable evaporation process and excellent film refractive index. To ensure stable performance and excellent film properties during the titanium niobium oxide evaporation process, the evaporator must have uniform particle size, high density, and high purity.

[0003] In recent years, China's optical industry has developed rapidly, with increasingly higher performance requirements and greater demand for evaporation materials in the high-end sector. However, the titanium niobium oxide evaporation materials produced by existing technologies have uneven particle shapes, low purity, and low density, making them suitable only for general low-end coating industries and unable to meet the quality requirements of high-end optical coating industries.

[0004] Therefore, developing high-density, uniformly sized, high-purity, high-yield titanium niobium oxide evaporation materials that meet market requirements can broaden market development. To this end, there is a need to provide a titanium niobium oxide coating material, its preparation method, and its applications. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a titanium niobium oxide coating material, its preparation method and application. The preparation method can realize the preparation of titanium niobium oxide coating material and can obtain titanium niobium oxide coating material with high purity, high density, uniform particle size and high yield.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for preparing a titanium niobium oxide coating material, the method comprising the following steps:

[0008] (1) Mix titanium pentoxide, niobium pentoxide, binder, thickener and solvent to obtain a slurry;

[0009] (2) The slurry obtained in step (1) is spray granulated to obtain powder with a particle size D50 of less than 45 μm;

[0010] (3) After the powder obtained in step (2) is debinded, it is made into a green body by cold isostatic pressing, and then crushed to obtain crushed particles;

[0011] (4) The crushed particles obtained in step (3) are sintered without pressure to obtain the titanium niobium oxide coating material.

[0012] The preparation method provided by this invention first obtains powder with a particle size D50 of less than 45 μm through spray granulation, then crushes it after cold isostatic pressing, and finally performs pressureless sintering. The resulting titanium niobium oxide coating material has the characteristics of high purity, high density, uniform particle size, and high yield. Specifically, the titanium pentoxide powder and niobium pentoxide powder can be fully mixed to maintain a uniform composition distribution. The cold isostatic pressing method can increase the green density and promote sintering densification, thus ensuring the optical performance of the high-density evaporation material after deposition. Simultaneously, the cold isostatic pressing followed by crushing reduces the occurrence of excessively small particles during crushing, thereby increasing the yield and reducing production costs.

[0013] Preferably, the mass of niobium pentoxide in step (1) is 1-5 wt% of the mass of titanium pentoxide, for example, it can be 1 wt%, 2 wt%, 3 wt%, 4 wt% or 5 wt%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0014] Preferably, the mass of the binder is 2-8 wt% of the total mass of titanium pentoxide and niobium pentoxide in step (1), for example, it can be 2 wt%, 4 wt%, 5 wt%, 6 wt% or 8 wt%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0015] Preferably, the mass of the thickener is 0.2-1 wt% of the total mass of titanium pentoxide and niobium pentoxide in step (1), for example, it can be 0.2 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.8 wt% or 1 wt%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0016] Preferably, the mass of the solvent is 100-150 wt% of the total mass of titanium pentoxide and niobium pentoxide in step (1), for example, it can be 100 wt%, 110 wt%, 120 wt%, 130 wt%, 140 wt% or 150 wt%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0017] As a preferred technical solution of the present invention, the mixing in step (1) includes: ball milling to uniformly mix titanium pentoxide and niobium pentoxide, then adding binder, thickener and solvent, and continuing to ball mill and mix until uniform.

[0018] Preferably, the adhesive in step (1) comprises polyvinyl alcohol (PVA) and / or polyvinyl butyral (PVB).

[0019] Preferably, the thickener in step (1) includes polyacrylamide.

[0020] Preferably, the solvent in step (1) includes water.

[0021] Preferably, the temperature for discharging adhesive in step (3) is 350-600℃, for example, it can be 350℃, 400℃, 450℃, 500℃, 550℃ or 600℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0022] Preferably, the glue removal time in step (3) is 6-12 hours, for example, it can be 6 hours, 8 hours, 9 hours, 10 hours or 12 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0023] This invention ensures a low carbon content in the resulting titanium niobium oxide coating material through adhesive removal.

[0024] Preferably, the preparation method further includes sieving after glue removal and before cold isostatic pressing. The mesh size of the sieve is 270-400 mesh, for example, 270 mesh, 300 mesh, 325 mesh, 350 mesh or 400 mesh, but not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 325 mesh.

[0025] Preferably, the pressure of the cold isostatic pressing in step (3) is 50-100 MPa, for example, it can be 50 MPa, 60 MPa, 80 MPa, 90 MPa or 100 MPa, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0026] Preferably, the pressureless sintering in step (4) includes a first heating, a first holding, a second heating, a second holding, a third heating, and a third holding in sequence.

[0027] Preferably, the endpoint temperature of the first heating is 700-900℃, for example, it can be 700℃, 750℃, 800℃, 850℃ or 900℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0028] Preferably, the first heat preservation time is 1-2 hours, for example, it can be 1 hour, 1.2 hours, 1.5 hours, 1.6 hours, 1.8 hours or 2 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0029] Preferably, the endpoint temperature of the second heating is 1100-1200℃, for example, it can be 1100℃, 1120℃, 1150℃, 1180℃ or 1200℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0030] Preferably, the second heat preservation time is 1-2 hours, for example, it can be 1 hour, 1.2 hours, 1.5 hours, 1.6 hours, 1.8 hours or 2 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0031] Preferably, the endpoint temperature of the third heating is 1300-1450℃, for example, it can be 1300℃, 1320℃, 1350℃, 1380℃, 1400℃, 1420℃ or 1450℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0032] Preferably, the third heat preservation time is 3-5 hours, for example, it can be 3 hours, 3.5 hours, 4 hours, 4.5 hours or 5 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0033] Preferably, the preparation method of titanium pentoxide in step (1) includes the following steps:

[0034] Titanium powder and titanium dioxide powder are mixed and then calcined to obtain titanium pentoxide.

[0035] Preferably, the mass ratio of titanium powder to titanium dioxide powder is 1:(6.5-8.5), for example, it can be 1:6.5, 1:7, 1:7.5, 1:8 or 1:8.5, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0036] Preferably, the particle size of the titanium powder is less than 10 μm.

[0037] Preferably, the particle size of the titanium dioxide powder is less than 10 μm.

[0038] This invention does not specifically limit the particle size of titanium powder or titanium dioxide powder, as long as the particle size of titanium powder and titanium dioxide powder are both below 10 μm.

[0039] Preferably, the titanium powder and titanium dioxide powder are mixed using a V-type mixer. To ensure uniform mixing, the mixing time is more than 24 hours, and the mixing ratio of the powder to the powder is (5-10):1, for example, it can be 5:1, 6:1, 8:1, 9:1 or 10:1, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0040] Preferably, the calcination is carried out under vacuum conditions, including a first calcination, a second calcination, and a third calcination performed sequentially.

[0041] Preferably, the vacuum degree of the vacuum condition is ≤10. -3 Pa.

[0042] Preferably, the temperature of the first calcination is 800-1000℃, for example, it can be 800℃, 850℃, 900℃, 950℃ or 1000℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0043] Preferably, the holding time for the first calcination is 2-4 hours, for example, it can be 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0044] Preferably, the second calcination temperature is 1150-1300℃, for example, it can be 1150℃, 1180℃, 1200℃, 1250℃, 1280℃ or 1300℃, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0045] Preferably, the heat preservation time for the second calcination is 2-4 hours, for example, it can be 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0046] Preferably, the temperature of the third calcination is 1400-1550℃, for example, it can be 1400℃, 1420℃, 1450℃, 1500℃ or 1550℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0047] Preferably, the holding time for the third calcination is 1-3 hours, for example, it can be 1 hour, 1.5 hours, 2 hours, 2.5 hours or 3 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0048] In a second aspect, the present invention provides a titanium niobium oxide coating material, which is obtained by the preparation method described in the first aspect.

[0049] Thirdly, the present invention provides an application of the titanium niobium oxide coating material as described in the second aspect, wherein the titanium niobium oxide coating material is used for evaporation coating.

[0050] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0051] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0052] The preparation method provided by this invention first obtains powder with a particle size D50 of less than 45 μm through spray granulation, then crushes it after cold isostatic pressing, and finally performs pressureless sintering. The resulting titanium niobium oxide coating material has the characteristics of high purity, high density, uniform particle size, and high yield. Among them, titanium pentoxide powder and niobium pentoxide powder can be fully mixed to maintain uniform component distribution. The cold isostatic pressing method can improve the green density and promote sintering densification to ensure the optical performance of the high-density evaporation material after deposition. At the same time, the cold isostatic pressing followed by crushing can reduce the occurrence of excessively small particles during crushing, thereby improving the yield and reducing production costs. Detailed Implementation

[0053] The technical solution of the present invention will be further illustrated below through specific embodiments.

[0054] To clearly illustrate the technical solution of the present invention, the titanium powder particle size in the specific embodiments of the present invention is less than 10 μm, the titanium dioxide powder particle size is less than 10 μm, and the purity is ≥99.99 wt%.

[0055] Example 1

[0056] This embodiment provides a method for preparing a titanium niobium oxide coating material, the method comprising the following steps:

[0057] (1) In a V-type powder mixer, titanium powder and titanium dioxide powder are uniformly mixed at a mass ratio of 1:7.5, and then the mixture is subjected to a vacuum of 10. -3 Under the condition of Pa, the first calcination, the second calcination and the third calcination were carried out in sequence to obtain titanium pentoxide;

[0058] The ratio of the mixed material to the pellets is 8:1;

[0059] The first calcination temperature is 900℃ and the holding time is 3 hours; the second calcination temperature is 1200℃ and the holding time is 3 hours; the third calcination temperature is 1500℃ and the holding time is 2 hours.

[0060] (2) Ball mill the titanium pentoxide and niobium pentoxide evenly, then add binder, thickener and solvent, and continue ball milling until uniform to obtain slurry;

[0061] The mass of niobium pentoxide is 3 wt% of the mass of titanium pentoxide;

[0062] Based on the total mass of titanium pentoxide and niobium pentoxide as m, the mass of the binder is 5 wt% of m; the mass of the thickener is 0.5 wt% of m; and the mass of the solvent is 120 wt% of m.

[0063] The binder is commercially available polyvinyl alcohol, the thickener is commercially available polyacrylamide, and the solvent is water;

[0064] (3) The slurry obtained in step (2) is spray-granulated to obtain powder with a particle size D50 of 30μm;

[0065] (4) After the powder obtained in step (3) is debinded, it is passed through a 325-mesh sieve, cold isostatic pressing is used to make green bodies, and then crushed to obtain crushed particles;

[0066] The temperature for degreasing is 450℃, and the time is 9 hours.

[0067] The pressure of the cold isostatic pressing is 75 MPa;

[0068] (5) The crushed particles obtained in step (4) are subjected to a first heating, a first holding, a second heating, a second holding, a third heating and a third holding in sequence. Then, the material under a 5-mesh sieve and the material over a 12-mesh sieve are taken to obtain the titanium niobium oxide coating material.

[0069] The final temperature of the first heating is 800℃, and the time is 1.5h;

[0070] The final temperature of the second heating process was 1150℃, and the time was 1.5 hours.

[0071] The final temperature of the third heating step is 1400℃, and the time is 4 hours.

[0072] Example 2

[0073] This embodiment provides a method for preparing a titanium niobium oxide coating material, the method comprising the following steps:

[0074] (1) In a V-type powder mixer, titanium powder and titanium dioxide powder are uniformly mixed at a mass ratio of 1:6.5, and then the mixture is subjected to a vacuum of 10. -3 Under the condition of Pa, the first calcination, the second calcination and the third calcination were carried out in sequence to obtain titanium pentoxide;

[0075] The ratio of the mixed material to the pellets is 5:1;

[0076] The first calcination temperature is 800℃ and the holding time is 4 hours; the second calcination temperature is 1150℃ and the holding time is 4 hours; the third calcination temperature is 1400℃ and the holding time is 3 hours.

[0077] (2) Ball mill the titanium pentoxide and niobium pentoxide evenly, then add binder, thickener and solvent, and continue ball milling until uniform to obtain slurry;

[0078] The mass of niobium pentoxide is 1 wt% of the mass of titanium pentoxide;

[0079] Based on the total mass of titanium pentoxide and niobium pentoxide as m, the mass of the binder is 2 wt% of m; the mass of the thickener is 0.2 wt% of m; and the mass of the solvent is 100 wt% of m.

[0080] The binder is commercially available polyvinyl alcohol, the thickener is commercially available polyacrylamide, and the solvent is water;

[0081] (3) The slurry obtained in step (2) is spray-granulated to obtain powder with a particle size D50 of 30μm;

[0082] (4) After the powder obtained in step (3) is debinded, it is passed through a 325-mesh sieve, cold isostatic pressing is used to make green bodies, and then crushed to obtain crushed particles;

[0083] The temperature for glue removal is 350℃, and the time is 12 hours.

[0084] The pressure of the cold isostatic pressing is 50 MPa;

[0085] (5) The crushed particles obtained in step (4) are subjected to a first heating, a first holding, a second heating, a second holding, a third heating and a third holding in sequence. The material under a 5-mesh sieve and the material over a 12-mesh sieve are taken to obtain the titanium niobium oxide coating material.

[0086] The final temperature of the first heating is 700℃, and the time is 2 hours;

[0087] The final temperature of the second heating process was 1100℃, and the time was 2 hours.

[0088] The final temperature of the third heating step is 1300℃, and the time is 5 hours.

[0089] Example 3

[0090] This embodiment provides a method for preparing a titanium niobium oxide coating material, the method comprising the following steps:

[0091] (1) In a V-type powder mixer, titanium powder and titanium dioxide powder are uniformly mixed at a mass ratio of 1:8.5, and then the mixture is subjected to a vacuum of 10. -3 Under the condition of Pa, the first calcination, the second calcination and the third calcination were carried out in sequence to obtain titanium pentoxide;

[0092] The ratio of the mixed material to the pellets is 10:1;

[0093] The first calcination temperature is 1000℃, and the holding time is 2 hours; the second calcination temperature is 1300℃, and the holding time is 2 hours; the third calcination temperature is 1550℃, and the holding time is 1 hour.

[0094] (2) Ball mill the titanium pentoxide and niobium pentoxide evenly, then add binder, thickener and solvent, and continue ball milling until uniform to obtain slurry;

[0095] The mass of niobium pentoxide is 5 wt% of the mass of titanium pentoxide;

[0096] Based on the total mass of titanium pentoxide and niobium pentoxide as m, the mass of the binder is 8 wt% of m; the mass of the thickener is 1 wt% of m; and the mass of the solvent is 150 wt% of m.

[0097] The binder is commercially available polyvinyl alcohol, the thickener is commercially available polyacrylamide, and the solvent is water;

[0098] (3) The slurry obtained in step (2) is spray-granulated to obtain powder with a particle size D50 of 30μm;

[0099] (4) After the powder obtained in step (3) is debinded, it is passed through a 325-mesh sieve, cold isostatic pressing is used to make green bodies, and then crushed to obtain crushed particles;

[0100] The temperature for degreasing is 600℃, and the time is 6 hours.

[0101] The pressure of the cold isostatic pressing is 100 MPa;

[0102] (5) The crushed particles obtained in step (4) are subjected to a first heating, a first holding, a second heating, a second holding, a third heating and a third holding in sequence. The material under a 5-mesh sieve and the material over a 12-mesh sieve are taken to obtain the titanium niobium oxide coating material.

[0103] The final temperature of the first heating is 900℃, and the time is 1 hour;

[0104] The final temperature of the second heating process is 1200℃, and the time is 1 hour.

[0105] The final temperature of the third heating step is 1450℃, and the time is 3 hours.

[0106] Example 4

[0107] This embodiment provides a method for preparing a titanium niobium oxide coating material. Except for the absence of a first calcination when preparing titanium pentoxide, the method is the same as in Example 1.

[0108] Example 5

[0109] This embodiment provides a method for preparing a titanium niobium oxide coating material. Except for the absence of a second calcination during the preparation of titanium pentoxide, the method is the same as in Example 1.

[0110] Example 6

[0111] This embodiment provides a method for preparing a titanium niobium oxide coating material, which is the same as in Embodiment 1 except that the first heating and the first heat preservation are not performed.

[0112] Example 7

[0113] This embodiment provides a method for preparing a titanium niobium oxide coating material, which is the same as in Example 1 except that the second heating and second heat preservation are not performed.

[0114] Comparative Example 1

[0115] This comparative example provides a method for preparing a titanium niobium oxide coating material, which is the same as that in Example 1 except that cold isostatic pressing is not performed.

[0116] Performance Characterization

[0117] The density and particle size uniformity of the titanium niobium oxide coating materials obtained in Examples 1-7 and Comparative Example 1 were tested, and the results are shown in Table 1. Density was tested using a porosity analyzer; uniformity was expressed as yield, which refers to the proportion of material passing through a 5-mesh sieve and a 12-mesh sieve (the material passing through both 5-mesh and 12-mesh sieves) to the total obtained material.

[0118] Table 1

[0119] Density (%) Uniformity Yield (%) Example 1 99 uniform 95 Example 2 98 uniform 93 Example 3 99 uniform 95 Example 4 90 Uneven 80 Example 5 91 Uneven 81 Example 6 92 Uneven 79 Example 7 90 Uneven 76 Comparative Example 1 Unformed Uneven 0

[0120] In summary, the preparation method provided by this invention first obtains powder with a particle size D50 of less than 45 μm through spray granulation, then crushes it after cold isostatic pressing, and finally performs pressureless sintering. The resulting titanium niobium oxide coating material has the characteristics of high purity, high density, uniform particle size, and high yield. Among them, titanium pentoxide powder and niobium pentoxide powder can be fully mixed to maintain uniform composition distribution. The cold isostatic pressing method can improve the green density and promote sintering densification to ensure the optical performance of the high-density evaporation material after deposition. At the same time, the cold isostatic pressing followed by crushing can reduce the occurrence of excessively small particles during crushing, thereby improving the yield and reducing production costs.

[0121] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a titanium niobium oxide coating material, characterized in that, The preparation method includes the following steps: (1) A slurry is obtained by mixing titanium pentoxide, niobium pentoxide, binder, thickener, and solvent; the mass of niobium pentoxide is 1-5 wt% of the mass of titanium pentoxide; the preparation method of titanium pentoxide includes the following steps: mixing titanium powder and titanium dioxide powder, and then calcining to obtain titanium pentoxide; the calcination is carried out under vacuum conditions, including a first calcination, a second calcination, and a third calcination performed sequentially; the vacuum degree of the vacuum conditions is ≤10. -3 Pa; the first calcination temperature is 800-1000℃, and the holding time is 2-4h; the second calcination temperature is 1150-1300℃, and the holding time is 2-4h; the third calcination temperature is 1400-1550℃, and the holding time is 1-3h. (2) The slurry obtained in step (1) is spray-granulated to obtain powder with a particle size D50 of less than 45 μm; (3) After the powder obtained in step (2) is debinded, it is made into a green body by cold isostatic pressing, and then crushed to obtain crushed particles; the debinding temperature is 350-600℃; the debinding time is 6-12h; (4) The crushed particles obtained in step (3) are sintered without pressure to obtain the titanium niobium oxide coating material; The pressureless sintering includes a first heating, a first holding, a second heating, a second holding, a third heating, and a third holding in sequence; The final temperature of the first heating is 700-900℃; the first holding time is 1-2 hours. The final temperature of the second heating is 1100-1200℃; the second holding time is 1-2 hours. The final temperature of the third heating is 1300-1450℃; the third holding time is 3-5 hours.

2. The preparation method according to claim 1, characterized in that, Based on the total mass of titanium pentoxide and niobium pentoxide in step (1) as m, the mass of the binder is 2-8 wt% of m.

3. The preparation method according to claim 1, characterized in that, Based on the total mass of titanium pentoxide and niobium pentoxide in step (1) as m, the mass of the thickener is 0.2-1 wt% of m.

4. The preparation method according to claim 1, characterized in that, Based on the total mass of titanium pentoxide and niobium pentoxide in step (1) as m, the mass of the solvent is 100-150 wt% of m.

5. The preparation method according to claim 1, characterized in that, The adhesive in step (1) includes polyvinyl alcohol and / or polyvinyl butyral.

6. The preparation method according to claim 1, characterized in that, The thickener in step (1) includes polyacrylamide.

7. The preparation method according to claim 1, characterized in that, The solvent in step (1) includes water.

8. The preparation method according to claim 1, characterized in that, The pressure of the cold isostatic pressing in step (3) is 50-100 MPa.

9. The preparation method according to claim 1, characterized in that, The mass ratio of titanium powder to titanium dioxide powder is 1:(6.5-8.5).

10. The preparation method according to claim 1, characterized in that, The particle size of the titanium powder is less than 10 μm.

11. The preparation method according to claim 1, characterized in that, The particle size of the titanium dioxide powder is less than 10 μm.

12. A titanium niobium oxide coating material, characterized in that, The titanium niobium oxide coating material is obtained by the preparation method described in any one of claims 1-11.

13. An application of the titanium niobium oxide coating material as described in claim 12, characterized in that, The titanium niobium oxide coating material is used for evaporation coating.