Black pigment for Ce-V series ceramic substrate, preparation method and application

Abstract

The invention relates to the technical field of ceramic substrates, in particular to a black pigment for a Ce-V series ceramic substrate and a preparation method and application thereof.The black pigment for the Ce-V series ceramic substrate is prepared from CeO2, V2O5 and NaCl through a solid-phase method, and solid-phase reaction products comprise CeVO4, V2O3, VO2, Ce4O7 and NaClO4; the black pigment for the Ce-V series ceramic substrate does not contain heavy metal elements, so that the harm of the heavy metal elements to a human body in actual production is avoided; the natural color material still has a good color generation effect at the high temperature of 1000-1600 DEG C; the aluminum oxide black porcelain added with the natural color material meets the requirements of packaging ceramics in electrical properties, such as volume resistivity; the natural color material can be applied to the preparation of various ceramic substrates, such as aluminum oxide, zirconium oxide, aluminum nitride and the like, and has a wide application range.

Description

Technical Field

[0001] The present invention relates to the technical field of ceramic substrates, and in particular to a black colorant for a Ce-V series ceramic substrate, a preparation method and an application thereof. Background Art

[0002] With the rapid development of new energy vehicles, drones, electronic communications and other industries, in order to meet the needs of these industries for high-power, small-size and highly integrated substrates, alumina ceramic substrates have been widely used in these industries due to their excellent mechanical properties, electrical properties, thermal properties and other characteristics; black alumina ceramic substrates are ceramic substrates designed and prepared on this basis to meet the needs of photosensitivity, among which black colorant is an important component in black alumina ceramics, which is used to determine the final coloring effect of black alumina ceramic substrates; since black alumina ceramic substrates are materials used in the application field of electronic components, the selection of black colorant must take into account the performance of black alumina ceramic substrates, such as high volume resistivity, high mechanical strength and pure blackness.

[0003] At present, the common black pigments used for ceramic substrates on the market include Fe2O3, CoO, Cr2O3 and MnO. These black pigments contain a large amount of heavy metal elements, which can cause harm to the human body during the actual production process.

[0004] In order to solve the above technical problems, the technical solution disclosed in the Chinese invention patent with patent application number CN202410465801.9 is a black pigment for ceramic substrates and its preparation method and application. The black pigment for ceramic substrates includes the following raw materials in molar mass fractions: 1 to 3 parts of V2O5, 3 to 5 parts of Al2O3, 1 to 3 parts of Sm2O3, 0.5 to 4 parts of Y2O3, 0.5 to 4 parts of Cr2O3, and 0.5 to 4 parts of Fe2O3. The black pigment for ceramic substrates is prepared by a solid phase method. The black pigment provided by the present invention is a cobalt-free pigment with low cost, and the content of heavy metals contained in the black pigment is low, which has low harm to the human body in actual production; the black ceramics added with this pigment have good coloring effect and color stability at high temperatures of 1000°C to 1600°C; the black ceramics added with this pigment meet the requirements of packaging ceramics in terms of electrical properties, such as volume resistivity. The black colorant of the present invention can be applied to the preparation of various black ceramics, such as packaging ceramics such as aluminum oxide, zirconium oxide, and aluminum nitride, and has a wide range of applications.

[0005] However, the above-mentioned prior art has the following technical problems: the black colorant used in the above-mentioned ceramic substrate only reduces the content of heavy metals, and still uses two heavy metals, Cr2O3 and Fe2O3, as raw materials, which will still cause harm to the human body in actual production. Summary of the invention

[0006] In view of this, it is necessary to provide a black colorant for Ce-V series ceramic substrates, a preparation method and an application thereof, which does not use heavy metals as raw materials at all, thereby avoiding the harm of heavy metal elements to the human body in actual production.

[0007] In a first aspect, the present invention provides a black colorant for a Ce-V ceramic substrate, comprising the following raw materials in molar mass fractions: 0.8 to 1.4 mol fraction of CeO2, 0.2 to 1.0 mol fraction of V2O5 and 0.1 to 0.4 mol fraction of NaCl.

[0008] In a second aspect, the present invention provides a method for preparing a black pigment for a Ce-V ceramic substrate according to the first aspect, comprising the following steps:

[0009] S1, CeO2, V2O5 and NaCl are mixed in proportion and then ball-milled, and the product after ball-milling is dried, ground and sieved to obtain a yellowish brown powder;

[0010] S2, sintering the khaki powder in a muffle furnace to obtain a black pigment block;

[0011] S3, the black pigment block is ground, crushed, ball-milled and sieved to obtain the black pigment.

[0012] Preferably, S1 comprises: adding a mixture of CeO2, V2O5 and NaCl into grinding balls according to a predetermined material ratio and grinding for a first predetermined time.

[0013] Preferably, the step S1 includes: drying at 100° C. for a second predetermined time.

[0014] Preferably, S2 includes: the sintering process is to first sinter the khaki powder at a predetermined temperature for a third predetermined time, and then take it out after cooling it to room temperature in the furnace.

[0015] Preferably, when performing the "ball milling mixing" in S1 and the "ball milling treatment" in S3, the ball mill used is a planetary ball mill, the ball mill jar used is a corundum ball mill jar, the grinding balls used are corundum ceramic grinding balls, and the ball milling medium used is deionized water.

[0016] In a third aspect, the present invention provides an application of a black colorant for a Ce-V series ceramic substrate in the production of a high resistivity black ceramic substrate. The black colorant for a Ce-V series ceramic substrate is the black colorant for a Ce-V series ceramic substrate described in the first aspect, or is prepared by the preparation method described in the second aspect.

[0017] Preferably, the production of the high resistivity black ceramic substrate includes: mixing the black colorant for the Ce-V series ceramic substrate with the encapsulated ceramic powder in a specific proportion, then adding an organic additive to carry out ball milling, vacuum degassing after the ball milling mixture is completed, casting on a casting machine, drying, debinding, and sintering to obtain a black ceramic substrate; wherein the weight of the black colorant for the Ce-V series ceramic substrate is 5%wt~15wt% of the total weight of the encapsulated ceramic powder.

[0018] Preferably, the packaged ceramic powder includes any one of aluminum oxide, zirconium oxide and aluminum nitride.

[0019] Preferably, the organic additives include solvents, dispersants, binders and plasticizers; the ball milling mixing includes two stages of mixing, the first stage of mixing is to evenly mix the black colorant, alumina powder, solvent and dispersant for the Ce-V series ceramic substrate; the second stage of mixing is to add a binder and a plasticizer and then mix evenly.

[0020] In the above-mentioned black pigment for Ce-V series ceramic substrate, CeO2, V2O5 and NaCl are used as mineralizers to prepare the black pigment for Ce-V series ceramic substrate through solid phase reaction. The products of the solid phase reaction include CeVO4, V2O3, VO2, Ce4O7 and NaClO4. Among them, the main coloring substances are CeVO4 and V2O3, which can make the black pigment for Ce-V series ceramic substrate have good coloring effect and coloring stability. Specifically, CeVO4, as a rare earth vanadate, has the characteristics of high stability and good crystallinity. The vanadate group absorbs visible light or transmits it to rare earth ions in the form of radiation transition, so that the rare earth ions can be formed. Soil ions also undergo electronic transitions to absorb visible light, thereby displaying a pure black color; V2O3 is a gray-black crystalline powder with a metallic luster, which is used to improve colorants and chromaticity; the black colorant for Ce-V series ceramic substrates provided by the present invention does not contain heavy metal elements, thereby avoiding the harm of heavy metal elements to the human body in actual production; the colorant still has a good coloring effect at high temperatures of 1000°C to 1600°C; the alumina black porcelain added with the colorant meets the requirements of packaging ceramics in terms of electrical properties, such as volume resistivity; the colorant can be used in the preparation of various ceramic substrates, such as alumina, zirconium oxide, aluminum nitride, etc., and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flow chart of a method for preparing a black colorant for a Ce-V series ceramic substrate of the present application.

[0022] Figure 2 This is a physical picture of four black porcelain substrate samples in Example 1 of the present application.

[0023] Figure 3It is the spectral reflectance curve of four black porcelain substrate samples in Example 1 of the present application.

[0024] Figure 4 It is the bandgap width curve of four black porcelain substrate samples in Example 1 of the present application.

[0025] Figure 5 It is the resistivity curve of the black porcelain substrate samples prepared with different amounts of colorant added in Example 2 of the present application.

[0026] Figure 6 It is the volume resistivity curve of the black porcelain substrate sample with a colorant addition amount of 10%wt at 20°C to 200°C in Example 2 of the present application.

[0027] Figure 7 Spectral reflectance curves of black colorant samples with different formulations in Example 3 of the present application.

[0028] Figure 8 This is a volume resistivity diagram of black pigment samples with different formulations in Example 3 of the present application. DETAILED DESCRIPTION

[0029] The technical solutions and technical effects of the embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings of the present invention.

[0030] In a first aspect, the present invention provides a black colorant for a Ce-V ceramic substrate, comprising the following raw materials in molar mass fractions: 0.8 to 1.4 mol fraction of CeO2, 0.2 to 1.0 mol fraction of V2O5 and 0.1 to 0.4 mol fraction of NaCl.

[0031] In a second aspect, the present invention provides a method for preparing a black pigment for a Ce-V ceramic substrate according to the first aspect, comprising the following steps:

[0032] S1, CeO2, V2O5 and NaCl are mixed in proportion and then ball-milled, and the product after ball-milling is dried, ground and sieved to obtain a yellowish brown powder;

[0033] S2, sintering the khaki powder in a muffle furnace to obtain a black pigment block;

[0034] S3, the black pigment block is ground, crushed, ball-milled and sieved to obtain the black pigment.

[0035] In this embodiment, adding NaCl as a mineralizer has the following beneficial effects:

[0036] 1. It can promote the occurrence of solid phase reaction. Specifically, it can reduce the temperature of synthesis reaction by forming active reaction groups and reducing the activation energy of the reaction;

[0037] 2. It can change the coordination environment of the coloring ions and improve the color performance of the pigment;

[0038] 3. It can strengthen the sintering process. Specifically, NaCl can promote the crystallization of porcelain clay during the sintering process, making ceramic products harder and more durable.

[0039] Further, S1 includes: adding a mixture of CeO2, V2O5 and NaCl into grinding balls according to a predetermined material ratio and grinding for a first predetermined time; specifically, the predetermined material ratio is 5:1, the first predetermined time is 4h, and the ball mill speed during the grinding process is 400rpm.

[0040] Further, S1 includes: when drying, drying at 100° C. for a second predetermined time, specifically, the second predetermined time is 5 to 8 hours;

[0041] In this embodiment, when sieving is performed in S1 and S3, the sieving mesh number is 300 meshes.

[0042] Furthermore, S2 includes: the sintering process is to first sinter the khaki powder at a predetermined temperature for a third predetermined time, and then take it out after cooling it to room temperature in the furnace. Specifically, the predetermined temperature is 1150°C, the heating rate is 5°C / min, and the third predetermined time is 30min.

[0043] In this embodiment, S3 can break up the agglomerates in the black colorant and reduce the particle size of the black colorant, thereby improving the color rendering performance of the black colorant.

[0044] Furthermore, when performing the "ball milling mixing" in S1 and the "ball milling treatment" in S3, the ball mill used is a planetary ball mill, the ball mill jar used is a corundum ball mill jar, the grinding balls used are corundum ceramic grinding balls, and the ball milling medium used is deionized water.

[0045] In a third aspect, the present invention provides an application of a black pigment for a Ce-V series ceramic substrate in the production of a high resistivity black ceramic substrate. The black pigment for a Ce-V series ceramic substrate is the black pigment for a Ce-V series ceramic substrate of the first aspect, or is prepared by the preparation method of the second aspect.

[0046] Furthermore, the production of high resistivity black ceramic substrate includes: mixing black colorant for Ce-V series ceramic substrate and encapsulated ceramic powder in a specific proportion, then adding organic additives to carry out ball milling mixing, vacuum degassing after the ball milling mixing is completed, casting on a casting machine, drying, debinding, and sintering to obtain a black ceramic substrate; wherein the weight of the black colorant for Ce-V series ceramic substrate is 5%wt~15wt% of the total weight of the encapsulated ceramic powder.

[0047] Furthermore, the packaged ceramic powder includes any one of aluminum oxide, zirconium oxide and aluminum nitride.

[0048] Furthermore, the organic additives include solvents, dispersants, binders and plasticizers; the ball milling mixing includes two stages of mixing, the first stage of mixing is to mix the Ce-V series ceramic substrate with black colorant, alumina powder, solvent and dispersant evenly to make the alumina powder evenly dispersed; the second stage of mixing is to add a binder and a plasticizer and then mix evenly to make a slurry.

[0049] Example 1: Experimental study on the effect of different proportions of V2O5 on the performance of black pigment for Ce-V ceramic substrates

[0050] Step 1: Prepare the following four mixed powders in different proportions:

[0051] The first part, CeO2, V2O5, NaCl in molar ratios of 1.0 mol component, 1.0 mol component, 0.1 mol component, total weight 10.0 g;

[0052] The second part, CeO2, V2O5, NaCl in molar proportions are 1.0 mol component, 0.2 mol component, 0.1 mol component, with a total weight of 9.06 g;

[0053] The third part, CeO2, V2O5, NaCl in molar proportions are 1.0 mol component, 0.5 mol component, 0.1 mol component, with a total weight of 9.37 g;

[0054] The fourth part, CeO2, V2O5, NaCl in molar proportions of 1.0 mol component, 2.0 mol component, 0.1 mol component, total weight of 10.26 g;

[0055] Step 2: put four portions of mixed powder into four ball milling jars respectively, add 50 g of grinding balls and 50 ml of deionized water, and mill in a planetary ball mill at 400 rpm for 4 h to fully mix the powders to obtain four portions of mixed powder slurries;

[0056] Step 3, drying the four mixed powder slurries at 100° C., grinding the larger particles in the powder, passing through a 300-mesh sieve and loading them into four crucibles respectively;

[0057] Step 4, placing four crucibles in a muffle furnace for sintering at a sintering temperature of 1150° C. for 30 minutes, and cooling with the furnace after the end of the insulation to obtain four portions of black pigment powder;

[0058] Step 5, the four portions of black pigment powder after sintering are respectively ball-milled, deionized water is added, and after ball-milling, they are dried at 100° C. and passed through a 300-mesh sieve to obtain four portions of black pigment, which are named A01, A02, A03 and A04 in order;

[0059] Step 6, weigh A01, A02, A03 and A04 respectively and mix them with alumina powder, the weight of the weighed black colorant is 5%wt~15wt% of the total weight of the alumina powder, add dispersant, binder, plasticizer, solvent and other organic additives, vacuum degassing after the mixing is complete, cast on a casting machine, dry, debind and sinter to obtain Figure 2 Four black porcelain substrate samples shown;

[0060] Step 7: Use an ultraviolet spectrophotometer to test the spectral reflectance curves of the four samples and obtain the following Figure 3 The four curves shown in Figure 2 are used to calculate the bandgap widths of the four samples using the Kubellka-Munk formula. Figure 4 The four curves shown in the figure are as follows: The volume resistivity of the four samples was measured and the data shown in the following table were obtained:

[0061] Table 1

[0062]

[0063] right Figure 3 The analysis shows that when the mixing ratio of Ce:V is 1:0.5, i.e. A03, the reflectance curve of the pigment is relatively smooth, indicating that the solid phase reaction is complete at this time. The reflectance curve of the pigment at other mixing ratios has obvious fluctuations, i.e. the color rendering performance is relatively poor, and the pigment appears gray-black.

[0064] right Figure 4 Analysis shows that A02, A03 and A04 are all black. Specifically, when Eg<1.8 eV, the material appears black.

[0065] From the analysis of Table 1, it can be seen that in the black pigment formula according to a certain molar ratio, the volume resistivity of the pigment obtained at room temperature is relatively high, all greater than 10 9 Ω·cm.

[0066] Example 2, comparison of resistivity of black ceramic substrates prepared by using black pigments with Ce-V ceramic substrates at different ratios:

[0067] The sample with the highest resistivity in Example 1, i.e. A03, was selected and added to alumina at a ratio of 5%wt to 15%wt to prepare 11 black porcelain substrate samples by tape casting. The resistivity test results of these samples are as follows:

[0068] Table 2

[0069]

[0070] According to Table 2, Figure 5 The resistivity curve shown in the figure shows that when the colorant addition amount is 10%wt, the resistivity of the black porcelain substrate sample is the highest; the volume resistivity of the black porcelain substrate sample with a colorant addition amount of 10%wt at 20℃~200℃ is measured, and the Figure 6 From the volume resistivity curve shown, it can be seen that the black porcelain substrate produced under this pigment addition ratio has a good volume resistivity at a temperature of 20°C to 200°C.

[0071] Example 3, performance comparison of black pigments with different formulations:

[0072] Four black pigment samples with different formulations of Fe-Cr, Fe-Cr-Mn, Ce-V and Fe-Cr-Ni-Mn were selected. The four black pigment samples were pressed into pigment blocks with a diameter of 10 mm and a thickness of 2.5 mm using a mold at a pressure of 5 tons for 40 seconds, and then sintered. The upper and lower surfaces of the sintered pigment blocks were ground to eliminate impurities on the surface of the pigment blocks, and then a layer of conductive silver paste was coated on the upper and lower surfaces. After being placed in an oven at 120°C for 30 minutes, four test samples were prepared;

[0073] The spectral reflectance curves of four test samples were tested by UV spectrophotometer, and the following results were obtained: Figure 7 From the analysis of the four curves shown, it can be seen that the Ce-V black pigment provided by the present invention has the lowest reflectivity, that is, the best chromaticity. Specifically, the pigment itself has a certain intrinsic frequency, and the light of these frequencies can be absorbed and radiated under appropriate conditions. When their intrinsic frequencies appear in the range of visible light, the pigment will show the corresponding color. There is a certain relationship between the absorption and reflection spectrum of a substance and the color seen, so the characteristics of the absorption or reflection curve of an object can identify the color and performance of the object. The lower the reflectivity of the black pigment, the more the sample absorbs, that is, the better the color.

[0074] Use an insulation resistance meter to apply a DC voltage of no more than 500V to the four test samples at room temperature. Read the resistance meter reading after 1 minute and convert the volume resistivity of the four test samples into the following formula:

[0075]

[0076] Where:

[0077] ρ v ---Volume resistivity of the sample / Ω·cm;

[0078] Rv ---Insulation resistance of the sample / Ω;

[0079] S---effective electrode area of ​​the sample / cm2;

[0080] H---thickness of the sample / cm;

[0081] The resistivity of the four test samples was prepared as Figure 8 From the volume resistivity graph shown, it can be seen that the Ce-V black pigment provided by the present invention has the highest volume resistivity, that is, the best electrical performance. Specifically, compared with black pigments of other formulations, the main product of the black pigment provided by the present invention is vanadate. The valence of V in the vanadate is fixed and stable, and it forms a structurally stable tetrahedral structure with O. In the stable tetrahedral structure, the arrangement of atoms or ions is fixed to form a relatively stable and compact structure, which will hinder the migration of charge carriers, requiring them to constantly change direction and overcome steric hindrance, resulting in an increase in the volume resistivity of the pigment; at the same time, the stable tetrahedral structure will affect the energy band structure inside the pigment, thereby affecting the volume resistivity of the pigment.

[0082] The black pigment for Ce-V ceramic substrate provided by the present invention has the following beneficial effects:

[0083] 1. Wide range of applications. It can be used to prepare various ceramic substrates, such as aluminum oxide, zirconium oxide, aluminum nitride and other packaging ceramic substrates;

[0084] 2. The color is stable and the high temperature stability is good. The black ceramics with this colorant still have good coloring effect at higher temperatures (1000℃~1600℃);

[0085] 3. The alumina black porcelain with this formula of pigment added meets the requirements of packaging ceramics in terms of electrical properties, such as volume resistivity;

[0086] 4. The raw materials are CeO2, V2O5 and NaCl, which do not contain heavy metal elements, thus avoiding the harm of heavy metal elements to the human body during the processing;

[0087] 5. Using CeO2 among rare earths as the material, because CeO2 is a rare earth resource with relatively large reserves and its price is relatively low among rare earth elements, it can make full use of my country's abundant rare earth resources and reduce production costs.

[0088] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A black pigment for a Ce-V ceramic substrate, characterized in that: The method comprises the following raw materials in molar mass fractions: 0.8-1.4 mol fraction of CeO2, 0.2-1.0 mol fraction of V2O5 and 0.1-0.4 mol fraction of NaCl.

2. A method for preparing a black pigment for a Ce-V ceramic substrate as claimed in claim 1, characterized in that: The following steps are involved: S1, CeO2, V2O5 and NaCl are mixed in proportion and then ball-milled, and the product after ball-milling is dried, ground and sieved to obtain a yellowish brown powder; S2, sintering the khaki powder in a muffle furnace to obtain a black pigment block; S3, the black pigment block is ground, crushed, ball-milled and sieved to obtain the black pigment.

3. The method for preparing a black pigment for a Ce-V ceramic substrate according to claim 2, characterized in that: The S1 comprises: adding a mixture of CeO2, V2O5 and NaCl into grinding balls according to a predetermined material ratio and grinding for a first predetermined time.

4. The method for preparing a black pigment for a Ce-V ceramic substrate according to claim 2, characterized in that: The step S1 includes: drying at 100° C. for a second predetermined time.

5. The method for preparing a black pigment for a Ce-V ceramic substrate according to claim 2, wherein: The S2 comprises: the sintering process is to first sinter the khaki powder at a predetermined temperature for a third predetermined time, and then take it out after cooling it to room temperature in the furnace.

6. The method for preparing a black pigment for a Ce-V ceramic substrate according to claim 2, characterized in that: When performing the "ball milling mixing" in S1 and the "ball milling treatment" in S3, the ball mill used is a planetary ball mill, the ball mill jar used is a corundum ball mill jar, the grinding balls used are corundum ceramic grinding balls, and the ball milling medium used is deionized water.

7. Application of a black pigment for a Ce-V series ceramic substrate in the production of a high resistivity black ceramic substrate, characterized in that: The black colorant for Ce-V series ceramic substrates is the black colorant for Ce-V series ceramic substrates as claimed in claim 1, or is prepared by the preparation method described in any one of claims 2 to 6.

8. The use of the black pigment for Ce-V series ceramic substrates as claimed in claim 7 in the production of high resistivity black ceramic substrates, characterized in that: The preparation of the high resistivity black ceramic substrate comprises: mixing a black colorant for a Ce-V series ceramic substrate with a packaged ceramic powder in a specific ratio, then adding an organic additive to perform ball milling, vacuum degassing after the ball milling, and performing tape casting on a tape casting machine, and obtaining a black ceramic substrate through drying, debinding, and sintering; wherein the weight of the black colorant for the Ce-V series ceramic substrate is 5%wt~15wt% of the total weight of the packaged ceramic powder.

9. The use of the black pigment for Ce-V series ceramic substrate as claimed in claim 8 in the production of high resistivity black ceramic substrate, characterized in that: The packaged ceramic powder includes any one of aluminum oxide, zirconium oxide and aluminum nitride.

10. The use of the black pigment for Ce-V series ceramic substrate as claimed in claim 8 in the production of high resistivity black ceramic substrate, characterized in that: The organic additives include solvents, dispersants, binders and plasticizers; the ball milling mixing includes two stages of mixing, the first stage of mixing is to evenly mix the black colorant, alumina powder, solvent and dispersant for the Ce-V series ceramic substrate; the second stage of mixing is to add binders and plasticizers and then mix evenly.

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