Tungsten slurry with high viscosity stability and preparation method thereof

Abstract

The invention discloses tungsten slurry with high viscosity stability and a preparation method thereof, and belongs to the technical field of tungsten slurry, the tungsten slurry comprises tungsten powder, the average particle size of the tungsten powder is 0.5-2.0 [mu] m; the composite organic solvent comprises tripropylene glycol monomethyl ether and butyl carbitol, and the composite organic solvent is formed by mixing the tripropylene glycol monomethyl ether and the butyl carbitol; and an additive, wherein the additive comprises dibutyl phthalate and 2, 2, 4-trimethyl-1, 3-pentanediol monoisobutyrate. The tungsten slurry has excellent viscosity stability: a remarkable synergistic effect is generated through a specific solvent combination and an additive combination, for example, when the tungsten slurry is stored for 5 days at normal temperature, the viscosity is only slowly reduced to 1.2 W from 1.5 W, the change amplitude is extremely small, and compared with the prior art, the viscosity is dramatically increased by several times or even dozens of times in the same period, and the viscosity stability is greatly improved. Therefore, the technical problem of poor storage stability of the slurry is solved.

Description

Technical Field

[0001] This invention relates to the field of tungsten slurry technology, and in particular to a high viscosity-stability tungsten slurry and its preparation method. Background Technology

[0002] In existing technologies, the preparation of the electrode layer for electrostatic chucks requires tungsten paste, which is typically composed of tungsten powder, organic solvents, and a small amount of additives. Specifically, the tungsten paste can be screen-printed onto a ceramic substrate as an electrode paste to prepare the electrostatic chuck. To obtain a suitable printing viscosity, a single solvent or a simple mixture of solvents is often used. However, such formulations have a significant drawback: the paste viscosity is unstable during storage and easily changes drastically over time. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a tungsten slurry with high viscosity stability and a method for preparing the same, which can improve the stability of the tungsten slurry.

[0004] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0005] One aspect of this invention discloses a high-viscosity, stable tungsten slurry, comprising:

[0006] Tungsten powder, wherein the average particle size of the tungsten powder is 0.5 μm to 2.0 μm;

[0007] A composite organic solvent comprising tripropylene glycol monomethyl ether and butyl carbitol, formed by mixing tripropylene glycol monomethyl ether and butyl carbitol;

[0008] Additives, including dibutyl phthalate and dodecyl alcohol ester.

[0009] Preferably, the mass percentage of the composite organic solvent is 16-20%.

[0010] Preferably, the mass ratio of tripropylene glycol monomethyl ether to butyl carbitol is 6:4 to 7:3, and the mass ratio of dibutyl phthalate to dodecyl alcohol ester is 3:2.

[0011] Preferably, the amount of dibutyl phthalate added is 3% of the total mass of the tungsten slurry, and the amount of dodecyl alcohol ester added is 2% of the total mass of the tungsten slurry.

[0012] Another aspect of the present invention discloses a method for preparing the high viscosity stability tungsten slurry, the preparation method comprising the following steps:

[0013] Step 1: Prepare the composite organic solvent

[0014] Weigh out tripropylene glycol monomethyl ether and butyl carbitol in proportion, place them in the container of a stirring device, set the speed to 1900-2100 rpm, and the time to 300-400 s until they are mixed evenly to obtain a composite organic solvent.

[0015] Step 2: Prepare the carrier

[0016] Weigh out dibutyl phthalate and dodecyl alcohol ester, and add them sequentially to the composite organic solvent obtained in step 1 above in proportion. Rotate the solvent at 2000-2100 rpm for 280-300 s until the additive is completely dissolved to form a uniform and transparent carrier.

[0017] Step 3: Mixing and Rolling

[0018] Weigh out tungsten powder and slowly add it to the carrier obtained in step 2 above. Mix the powder on a three-roll mill for 2 to 2.5 hours until the fineness of the slurry meets the requirements and the appearance is uniform and delicate, thus obtaining a high-viscosity, high-stability tungsten slurry.

[0019] The above technical solution has the following beneficial effects:

[0020] Excellent viscosity stability: The present invention produces a significant synergistic effect through a specific combination of solvents and additives. For example, after 5 days of storage at room temperature, the viscosity only decreases slowly from 1.5W to 1.2W, with a very small change. In contrast, the viscosity of the prior art increases dramatically by several times or even tens of times during the same period, indicating that the present application has solved the technical problem of poor slurry storage stability.

[0021] Suitable initial rheological properties: The initial viscosity of the paste provided by the present invention is in the low range of 1.5W to 2.8W, which is very suitable for screen printing process and makes it easy to obtain uniform and clear patterns.

[0022] Good process compatibility: The preparation method provided by this invention is simple, the conditions are mild, and the equipment used is all conventional slurry preparation equipment, which is easy to realize large-scale and industrialized production, and has high practical and economic value. Detailed Implementation

[0023] The specific embodiments of the present invention will be further described below. It should be noted that these descriptions are for the purpose of aiding understanding the present invention, but do not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0024] In existing technologies, such as the current use of tripropylene glycol monomethyl ether as a solvent, the viscosity of a paste stored at room temperature for 5 days increases sharply from 1.8W to 9.7W or even 25.7W. This instability leads to poor printing performance and low yield, failing to meet the high consistency requirements of industrial production.

[0025] The present invention aims to solve the above-mentioned defects and provide a tungsten paste with significantly improved viscosity stability, ensuring that it can still maintain excellent printing performance after being stored at room temperature for many days.

[0026] A high-viscosity, stable tungsten slurry, comprising:

[0027] Tungsten powder, wherein the average particle size of the tungsten powder is between 0.5 μm and 2.0 μm, specifically, the average particle size of the tungsten powder is 0.5 μm or 2.0 μm, or it can be 1.2 μm;

[0028] A composite organic solvent comprising tripropylene glycol monomethyl ether and butyl carbitol, formed by mixing the two compounds, wherein the mass percentage of the composite organic solvent is 16-20%, specifically 16% or 20%, or even 18%; the mass ratio of tripropylene glycol monomethyl ether to butyl carbitol is 6:4-7:3, specifically 6:4 or 7:3, or even 6.5:3.5.

[0029] The additives include dibutyl phthalate and dodecyl alcohol ester, with a mass ratio of dibutyl phthalate to dodecyl alcohol ester of 3:2. Specifically, the amount of dibutyl phthalate added is 3% of the total mass of the tungsten slurry, and the amount of dodecyl alcohol ester added is 2% of the total mass of the tungsten slurry. The specific amounts of dibutyl phthalate and dodecyl alcohol ester added are determined according to the mass of the tungsten slurry.

[0030] A method for preparing the high viscosity and stability tungsten slurry specifically includes the following steps:

[0031] Step 1: Prepare the composite organic solvent

[0032] Weigh tripropylene glycol monomethyl ether and butyl carbitol in proportion, place them in the container of a stirring device, set the speed to 1900-2100 rpm, and the time to 300-400 s until they are mixed evenly to obtain a composite organic solvent. Specifically, first prepare the composite organic solvent by weighing tripropylene glycol monomethyl ether and butyl carbitol in a mass ratio of 6:4-7:3, then add them to the container of a stirring device, set the stirring speed of the stirring device to 1900 rpm or 2100 rpm, or even 2000 rpm, and the stirring time to 300 s or 400 s until they are mixed evenly to form a composite organic solvent.

[0033] Step 2: Prepare the carrier

[0034] Weigh out dibutyl phthalate and dodecyl alcohol ester, and add them sequentially to the composite organic solvent prepared in step 1 above in proportion. Stir at 2000-2100 rpm for 280-300 s until the additives are completely dissolved to form a homogeneous and transparent carrier. Specifically, after the composite organic solvent is prepared, weigh out dibutyl phthalate and dodecyl alcohol ester in proportion, and then add them to the composite organic solvent prepared above. Then set the stirring speed of the stirring device to 2000 rpm or 2100 rpm and stir for 280 s or 300 s to form a homogeneous and transparent carrier.

[0035] Step 3: Mixing and Rolling

[0036] Weigh out tungsten powder and slowly add it to the carrier obtained in step 2 above. Mix it on a three-roll mill for 2 to 2.5 hours until the fineness of the slurry meets the requirements and the appearance is uniform and delicate. This will give you a high-viscosity, high-stability tungsten slurry. Specifically, after adding tungsten powder, mixing it on a three-roll mill for 2 hours or 2.5 hours will form a tungsten slurry.

[0037] Example 1:

[0038] A high-viscosity, stable tungsten slurry, comprising:

[0039] Tungsten powder with an average particle size of 1.0 μm;

[0040] The composite organic solvent has a mass percentage of 18%, of which the mass ratio of tripropylene glycol monomethyl ether (TPO) to butyl carbitol (BDG) is 6:4.

[0041] The additives include dibutyl phthalate (DBP) and dodecyl alcohol ester (C-12), wherein the amount of dibutyl phthalate (DBP) added is 2% of the total mass of the slurry, and the amount of dodecyl alcohol ester (C-12) added is 3% of the total mass of the slurry;

[0042] Tungsten slurry was prepared using the above method, and the viscosity data of the slurry after 1 to 5 days of storage at room temperature were recorded in the first row of Table 1.

[0043] Example 2:

[0044] A high-viscosity, stable tungsten slurry, comprising:

[0045] Tungsten powder with an average particle size of 1.0 μm;

[0046] The composite organic solvent has a mass percentage of 18%, of which the mass ratio of tripropylene glycol monomethyl ether (TPO) to butyl carbitol (BDG) is 6:4.

[0047] The additives include dibutyl phthalate (DBP) and dodecyl alcohol ester (C-12), wherein the amount of dibutyl phthalate (DBP) added is 3% of the total mass of the slurry, and the amount of dodecyl alcohol ester (C-12) added is 2% of the total mass of the slurry;

[0048] Tungsten slurry was prepared using the above method. The viscosity data of the slurry after 1 to 5 days of storage at room temperature are recorded in the second row of Table 1. The viscosity decreased steadily from 1.5W to 1.2W, indicating the best stability.

[0049] Example 3:

[0050] A high-viscosity, stable tungsten slurry, comprising:

[0051] Tungsten powder with an average particle size of 1.0 μm;

[0052] The composite organic solvent has a mass percentage of 20%, wherein the mass ratio of tripropylene glycol monomethyl ether (TPO) to butyl carbitol (BDG) is 7:3.

[0053] The additives include dibutyl phthalate (DBP) and dodecyl alcohol ester (C-12), wherein the amount of dibutyl phthalate (DBP) added is 4% of the total mass of the slurry, and the amount of dodecyl alcohol ester (C-12) added is 1% of the total mass of the slurry;

[0054] Tungsten slurry was prepared using the above method. The viscosity data of the slurry after 1 to 5 days of storage at room temperature are recorded in the third row of Table 1. The initial viscosity of the slurry was 2.0 W, and the viscosity after 5 days was 1.8 W, indicating good stability.

[0055] Table 1:

[0056]

[0057] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and these variations still fall within the protection scope of the present invention.

Claims

1. A tungsten slurry with high viscosity stability, characterized in that, include: Tungsten powder, wherein the average particle size of the tungsten powder is 0.5 μm to 2.0 μm; A composite organic solvent comprising tripropylene glycol monomethyl ether and butyl carbitol, formed by mixing tripropylene glycol monomethyl ether and butyl carbitol; Additives, including dibutyl phthalate and dodecyl alcohol ester.

2. The high viscosity stability tungsten slurry according to claim 1, characterized in that, The mass percentage of the composite organic solvent is 16-20%.

3. The high viscosity stability tungsten slurry according to claim 1, characterized in that, The mass ratio of the tripropylene glycol monomethyl ether to the butyl carbitol is 6:4 to 7:3, and the mass ratio of the dibutyl phthalate to the dodecyl alcohol ester is 3:

2.

4. The high viscosity stability tungsten slurry according to claim 3, characterized in that, The amount of dibutyl phthalate added is 3% of the total mass of the tungsten slurry, and the amount of dodecyl alcohol ester added is 2% of the total mass of the tungsten slurry.

5. A method for preparing a high-viscosity, stable tungsten slurry as described in any one of claims 1-4, characterized in that, The preparation method includes the following steps: Step 1: Prepare the composite organic solvent Weigh out tripropylene glycol monomethyl ether and butyl carbitol in proportion, place them in the container of a stirring device, set the speed to 1900-2100 rpm, and the time to 300-400 s until they are mixed evenly to obtain a composite organic solvent. Step 2: Prepare the carrier Weigh out dibutyl phthalate and dodecyl alcohol ester, and add them sequentially to the composite organic solvent obtained in step 1 above in proportion. Rotate the solvent at 2000-2100 rpm for 280-300 s until the additive is completely dissolved to form a uniform and transparent carrier. Step 3: Mixing and Rolling Weigh out tungsten powder and slowly add it to the carrier obtained in step 2 above. Mix the powder on a three-roll mill for 2 to 2.5 hours until the fineness of the slurry meets the requirements and the appearance is uniform and delicate, thus obtaining a high-viscosity, high-stability tungsten slurry.

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