High-toughness water-based ceramic slurry for LTCC and application

Abstract

The invention belongs to the technical field of low-temperature co-fired ceramics, and particularly relates to high-toughness water-based slurry for LTCC (Low Temperature Co-fired Ceramic) and application. The invention discloses an inorganic powder coating which comprises a binder, a dispersing agent, a plasticizer, inorganic powder and a solvent, the binder is polyether polyol, the dispersing agent is polyethylene glycol, polypropylene glycol, polybutylene glycol or polytetrahydrofuran, the plasticizer is butylene glycol, pentanediol or hexanediol, and the solvent is deionized water. According to the high-toughness water-based ceramic slurry for the LTCC, the advantages of high structural flexibility and good water solubility of the polyether polyol are utilized, the polyether polyol serves as an organic component of the water-based ceramic slurry, the problems that an existing water-based green ceramic chip is prone to cracking, low in adhesive force and the like are solved, and meanwhile the use performance of the LTCC is not affected.

Description

Technical Field

[0001] This invention belongs to the field of low-temperature co-fired ceramics technology, specifically relating to a high-toughness waterborne slurry for LTCC and its application. Background Technology

[0002] Low-temperature co-fired ceramic (LTCC) technology has been widely used in key fields such as communications, automotive electronics, aerospace, and consumer electronics due to its characteristics such as low sheet resistance of wiring conductors, high number of wiring layers, high wiring density, low sintering temperature, low dielectric loss, and excellent high-frequency performance, becoming an indispensable part of modern electronic component manufacturing.

[0003] The preparation process of LTCC typically involves the following steps: slurry preparation, casting, slicing, drilling, printing, lamination, pressurization, and debinding sintering. Among these, the composition of the slurry is the most important factor affecting the performance of LTCC. Because organoceramic slurries using toluene, ethyl acetate, or ethanol as solvents have better fluidity and dispersibility than water-based ceramic slurries, and the solvent evaporation rate is easier to control, they help reduce internal defects in green ceramic sheets and improve the quality of cast green ceramic sheets. Therefore, using organoceramic slurries to prepare LTCC remains the mainstream approach.

[0004] In recent years, with the increasing awareness of environmental protection, green chemistry has become an inevitable trend in the chemical industry, and the use of water-based ceramic slurries to replace organic ceramic slurries has become a research hotspot. Chinese patent CN117776739A provides a water-based low-temperature co-fired ceramic material and its preparation method. This method uses a mixture of polyacrylic acid aqueous solution and water-based acrylic emulsion as a binder, polyacrylamide as a dispersant, and glycerol as a plasticizer, resulting in a water-based casting slurry with high stability and good rheological properties. A summary of existing water-based ceramic slurry preparation processes shows that most water-based ceramic slurries use polyacrylate polymers or polyvinyl alcohol (PVA) as binders, sodium carboxymethyl cellulose and glycerol as plasticizers, and polyacrylamide and sodium polyacrylate as dispersants. These materials all have high polarity, resulting in green ceramic sheets that are more brittle and prone to cracking; they also have the problem of low adhesion to the release film, affecting the subsequent preparation of LTCC. Summary of the Invention

[0005] This invention provides a high-toughness waterborne ceramic slurry for LTCC and its application, in order to solve the technical problems of poor toughness and easy cracking of green ceramic sheets produced by waterborne ceramic slurry.

[0006] To solve the above-mentioned technical problems, the present invention provides a high-toughness waterborne ceramic slurry for LTCC, which includes a binder, a dispersant, a plasticizer, an inorganic powder, and a solvent. The binder is a polyether polyol, the dispersant is polyethylene glycol, polypropylene glycol, polybutanediol, or polytetrahydrofuran, the plasticizer is butanediol, pentanediol, or hexanediol, and the solvent is deionized water.

[0007] Polyether polyols exhibit excellent water solubility through hydrogen bonding with water, while the ether bonds in their structure provide excellent flexibility. The dispersants and plasticizers used are also non-ionic, and the content of polar groups is relatively low. Therefore, this is beneficial for preparing high-toughness waterborne green ceramic tiles, solving the problems of easy cracking and low adhesion to release films in existing waterborne green ceramic tiles.

[0008] Optionally, the polyether polyol is polyethylene glycol.

[0009] Optionally, the dispersant is polyethylene glycol.

[0010] Optionally, the molecular weight of the adhesive is 30,000-60,000 g / mol, preferably 40,000 g / mol.

[0011] Optionally, the molecular weight of the dispersant is 500-5000 g / mol, preferably 2400 g / mol.

[0012] Optionally, the inorganic powder comprises the following components by weight percentage:

[0013]

[0014] Optionally, the inorganic powder comprises the following components by weight percentage: 35

[0015] wt% CaO, 15wt% B2O3, 20wt% SiO2, 15wt% Al2O3, 5wt% MgO, 5wt% ZnO, 5wt% ZrO2.

[0016] Optionally, the mass ratio of the inorganic powder to the solvent is (1.1-1.4):1, preferably 1.25:1.

[0017] Optionally, the mass ratio of the dispersant to the inorganic powder is (0.3-0.7):100 or 0.5:100.

[0018] Optionally, the mass ratio of the binder to the inorganic powder is 1:(8-12.5), preferably 1:10.

[0019] Optionally, the mass ratio of the plasticizer to the binder is 1:(1.5-3.5), preferably 1:2.5.

[0020] Optionally, the preparation method of the high-toughness waterborne ceramic slurry for LTCC includes: first mixing inorganic powder and solvent, then adding dispersant for a first ball milling, and then adding binder and plasticizer for a second ball milling to obtain a uniform slurry.

[0021] Optionally, the first ball milling time is 10-15 hours and the rotation speed is 190-210 rpm; the second ball milling time is 10-15 hours and the rotation speed is 160-180 rpm.

[0022] The present invention also provides an LTCC waterborne green ceramic sheet, which is prepared by the above-mentioned LTCC high-toughness waterborne ceramic slurry through a casting process.

[0023] Compared with the prior art, the high-toughness waterborne ceramic slurry for LTCC provided by the present invention utilizes the advantages of polyether polyol itself, such as high structural flexibility and good water solubility, and uses polyether polyol as the organic component of waterborne ceramic slurry to solve the problems of easy cracking and low adhesion of current waterborne green ceramic tiles, while not affecting the performance of LTCC. Detailed Implementation

[0024] For ease of understanding, the following examples illustrate the high-toughness waterborne ceramic slurry for LTCC and its application. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0025] Example 1

[0026] The method for preparing the LTCC water-based green ceramic tile is as follows:

[0027] 1. Weigh the inorganic powder and mix it with deionized water. The preferred mass ratio of the inorganic powder to the deionized water is 1.25:1. The inorganic powder comprises the following components by weight percentage: 35wt% CaO, 15wt% B2O3, 20wt% SiO2, 15wt% Al2O3, 5wt% MgO, 5wt% ZnO, and 5wt% ZrO2.

[0028] 2. Weigh out the dispersant polyethylene glycol, the molecular weight of which is approximately 2400 g / mol, and the mass ratio of the dispersant to the inorganic powder is 0.5:100. Then add it to the mixture from step 1 and ball mill it for 12 hours at a speed of 200 rpm.

[0029] 3. Add polyethylene glycol binder to the slurry after the first ball milling. The binder has a molecular weight of approximately 40,000 g / mol and the mass ratio of the binder to the inorganic powder is 1:10. Add pentylene glycol plasticizer. The mass ratio of the plasticizer to the binder is 1:2.5. Perform a second ball milling for 12 hours at a speed of 170 rpm to obtain a stable and uniform high-toughness waterborne ceramic slurry for LTCC.

[0030] 4. The obtained LTCC is cast using a high-toughness waterborne ceramic slurry to obtain LTCC waterborne green ceramic sheets.

[0031] Example 2

[0032] The method for preparing the LTCC water-based green ceramic tile is as follows:

[0033] 1. Weigh out the inorganic powder and deionized water, wherein the mass ratio of the inorganic powder to the deionized water is 1.25:1, and the powder contains 35wt% CaO, 15wt% B2O3, 20wt% SiO2, 15wt% Al2O3, 5wt% MgO, 5wt% ZnO, and 5wt% ZrO2.

[0034] 2. Weigh out the dispersant polytetrahydrofuran, the molecular weight of which is approximately 2400 g / mol, and the mass ratio of the dispersant to the inorganic powder is 0.5:100. Then add it to the mixture from step 1 and ball mill it for 12 hours at a speed of 200 rpm.

[0035] 3. Add polyethylene glycol binder to the slurry after one ball milling. The binder has a molecular weight of approximately 40,000 g / mol and the mass ratio of the binder to the inorganic powder is 1:10. Add hexanediol plasticizer. The mass ratio of the plasticizer to the binder is 1:2.5. Perform a second ball milling for 12 hours at a speed of 170 rpm to obtain a stable and uniform high-toughness waterborne ceramic slurry for LTCC.

[0036] 4. The obtained LTCC is cast using a high-toughness waterborne ceramic slurry to obtain LTCC waterborne green ceramic sheets.

[0037] Comparative Example 1

[0038] The difference from Example 1 is that the adhesive used is polyvinyl alcohol (PVA) with a molecular weight of 40,000 g / mol.

[0039] Comparative Example 2

[0040] The difference from Example 1 is that the plasticizer is glycerol and the dispersant is polyacrylamide with a molecular weight of 2400 g / mol.

[0041] Performance testing

[0042] The cracking rate, elastic modulus and base film adhesion (green ceramic sheet peeling force) of the green ceramic sheets prepared in Examples 1-2 and Comparative Examples 1-2 were tested. The experimental results are shown in Table 1.

[0043] The cracking rate is calculated as follows: place the green ceramic tile on an LED inspection light and inspect it using backlighting. After 30 minutes, count the number of green ceramic tiles with cracks (a) and the total number of green ceramic tiles (b). Cracking rate = (a / b)%.

[0044] Test of elastic modulus GB / T 1040.3-2006.

[0045] The national standard reference for the base film adhesion (i.e., the peel strength of green ceramic tiles) test is GB / T2792-2014, and the test method is the method shown in Appendix B of GB / T 2792-2014.

[0046] Table 1

[0047]

[0048]

[0049] As shown in Table 1, the technical solution provided by the present invention effectively solves the problem of cracking of green ceramic tiles, and increases the elastic modulus by more than 45% and the peeling force of green ceramic tiles by more than double.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein, and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-toughness waterborne ceramic slurry for LTCC, characterized in that, The product comprises a binder, a dispersant, a plasticizer, an inorganic powder, and a solvent. The binder is a polyether polyol, the dispersant is polyethylene glycol, polypropylene glycol, polybutylene glycol, or polytetrahydrofuran, the plasticizer is butanediol, pentanediol, or hexanediol, and the solvent is deionized water.

2. The high-toughness waterborne ceramic slurry for LTCC according to claim 1, characterized in that, The polyether polyol is polyethylene glycol.

3. The high-toughness waterborne ceramic slurry for LTCC according to claim 1, characterized in that, The molecular weight of the adhesive is 30,000-60,000 g / mol, preferably 40,000 g / mol.

4. The high-toughness waterborne ceramic slurry for LTCC according to claim 3, characterized in that, The mass ratio of the binder to the inorganic powder is 1:(8-12.5), preferably 1:

10.

5. The high-toughness waterborne ceramic slurry for LTCC according to claim 4, characterized in that, The mass ratio of the plasticizer to the binder is 1:(1.5-3.5), preferably 1:2.

5.

6. The high-toughness waterborne ceramic slurry for LTCC according to claim 1, characterized in that, The dispersant has a molecular weight of 500-5000 g / mol, preferably 2400 g / mol.

7. The high-toughness waterborne ceramic slurry for LTCC according to claim 5, characterized in that, The mass ratio of the dispersant to the inorganic powder is (0.3-0.7):100, 0.5:

100.

8. The high-toughness waterborne ceramic slurry for LTCC according to claim 1, characterized in that, The mass ratio of the inorganic powder to the solvent is (1.1-1.4):1, preferably 1.25:

1.

9. The high-toughness waterborne ceramic slurry for LTCC according to claim 1, characterized in that, The preparation method of the high-toughness waterborne ceramic slurry for LTCC includes: first, mixing inorganic powder and solvent, then adding dispersant and ball milling once, then adding binder and plasticizer and ball milling a second time to obtain a uniform slurry.

10. A type of LTCC water-based green ceramic tile, characterized in that, The LTCC is prepared by casting process using the high-toughness waterborne ceramic slurry described in any one of claims 1-9.

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