Process method for improving cutting cracking of C0G type large-size high-capacity product

Abstract

The invention discloses a process method for improving cutting cracking of a C0G type large-size high-capacity product, and relates to the technical field of C0G type multilayer ceramic capacitors. In order to reduce the cutting cracking ratio of the product, PVB with higher molecular weight is selected as a binder, a concave screen printing plate is selected for printing, and a tempering process is added; the high-molecular-weight PVB is longer in molecular chain, stronger in physical entanglement effect, stronger in blade physical impact resistance and capable of inhibiting crack propagation, so that the anti-shearing efficiency of the ceramic membrane is remarkably improved, the binding force with the ceramic membrane can be enhanced, interlayer stress transfer during cutting is more uniform, the interlayer cracking risk is reduced, and the service life of the ceramic membrane is prolonged. And the cutting cracking condition of the product is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of C0G type multilayer ceramic capacitors, and specifically to a process method for improving the cutting cracking of large-size and high-capacitance C0G type products. Background Art

[0002] Generally speaking, the capacitance requirement for C0G generally does not exceed 10 nF. However, with the continuous development of the new energy wireless charging market, the demand for high-capacitance C0G type products (Cap≥10 nF) is increasing continuously; the selected ceramic powder has gradually developed from general large particle size and low dielectric constant (K<30) to small particle size and high dielectric constant (35<K<50). Such high-K value ceramic powders have a relatively high specific surface area BET due to their small particle size. If PVB (polyvinyl butyral) with a molecular weight of 30,000~50,000 is used according to the traditional formula, due to poor ceramic film adhesion and poor shear resistance, cutting cracking is likely to occur during cutting, which is particularly obvious in high-capacitance, high-layer, and large-size products.

[0003] Patent CN115572171A discloses a cutting and debinding process for chip high-capacitance multilayer ceramic capacitors. By performing heat treatment on the bar before cutting, the binder content is reduced to avoid cutting cracking caused by the friction between the blade and the cutting surface during cutting. However, in this solution, the main process that occurs to PVB at 200°C is physical processes such as solvent removal, and at this time, PVB has not decomposed (the decomposition temperature is 200~350°C). Therefore, in this solution, the PVB content does not decrease during heat treatment, and the cutting cracking phenomenon has not been completely solved during actual application.

[0004] Therefore, the present invention starts from three aspects: slurry formulation, screen printing design, and process flow, aiming to completely solve the problem of cutting cracking of large-size and high-capacitance C0G type products. Summary of the Invention

[0005] The purpose of the present invention is to provide a process method for improving the cutting cracking of large-size and high-capacitance C0G type products to solve the problems raised in the prior art.

[0006] To achieve the above purpose, the present invention provides the following technical solution: A process method for improving the cutting cracking of large-size and high-capacitance C0G type products, characterized by including the following steps: Step 1: Slurry preparation: Take ceramic powder, dispersant, solvent, high-molecular-weight PVB, and plasticizer, mix them evenly, and stir at high speed to obtain a slurry; Step 2: Take a ceramic film, and use a concave screen to print the first capacity electrode layer to obtain the first electrode ceramic film; take a ceramic film, and use a concave screen to print the second capacity electrode layer to obtain the second electrode ceramic film... take a ceramic film, and use a concave screen to print the capacity adjustment electrode layer to obtain the Nth electrode ceramic film; take N Nth electrode ceramic films coated with paste and stack them alternately in pairs to form a structure of "ceramic film-first electrode ceramic film-second electrode ceramic film...Nth electrode ceramic film-ceramic film", to obtain a laminated substrate (block); Step 3: Perform hydrostatic treatment on the laminated substrate (block), remove it after hydrostatic treatment, temper it under nitrogen atmosphere protection, and then cut it to obtain a large-size high-capacity C0G type product. In step 2, 5 < N < 300.

[0007] Furthermore, in step 1, the mass ratio of ceramic powder, dispersant, solvent, high molecular weight PVB, and plasticizer is 10: (0.1~0.3): (1.5~2.5): (2.0~3.0): (0.1~0.3).

[0008] Furthermore, in step 1, the dispersant is polyacrylamide; In step 1, the solvent is one or a mixture of ethanol, isopropanol, and toluene; In step 1, the plasticizer is one or a mixture of diisononyl phthalate, dioctyl phthalate, and diisodecyl phthalate.

[0009] Furthermore, in step 1, the molecular weight of the high molecular weight PVB is 50,000 to 100,000.

[0010] Furthermore, in step 1, the process conditions for high-speed stirring are: rotation speed 1000~1200 r / min, time 6~8 h.

[0011] Furthermore, in step 2, the thickness of the ceramic membrane is 5~10μm; In step 2, the printing thickness of the first capacity electrode layer, the second capacity electrode layer, and the capacity adjustment electrode layer is 0.5~2μm.

[0012] Furthermore, in step 3, during the tempering process, a PET film is placed between each laminated substrate as a release film to prevent the blocks from sticking together. The thickness of the PET film is 5~15μm.

[0013] Furthermore, in step 2, the coating thickness of the slurry is 10~20μm.

[0014] Furthermore, in step 2, the process conditions for water pressure treatment are: temperature 85~105℃, pressure 100~150MPa, heating rate 0.5~1.5℃ / min, and pressure rate 2~3MPa / min; In step 2, the tempering process conditions are: temperature 250~300℃, heating rate 2~3℃ / min, and tempering time 1.0~3.0h.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. Traditional low molecular weight PVB is prone to interlayer separation under blade impact, indicating that the ceramic film interface has weak shear resistance during cutting. Therefore, high molecular weight PVB is selected as the binder. High molecular weight PVB has longer molecular chains, stronger physical entanglement, and stronger resistance to physical impact from the blade. It can inhibit crack propagation and thus significantly improve the shear resistance of the ceramic film. In addition, high molecular weight PVB can enhance the bonding force between PVB and ceramic film, and the interlayer stress transfer during cutting is more uniform, reducing the risk of interlayer cracking.

[0016] 2. The glass transition temperature of PVB is approximately 60-70℃. Below 200℃, PVB is in a highly elastic state (softened and flowing state). At this temperature, increasing the temperature will cause a decrease in viscosity and promote interfacial penetration. Although the adhesive strength increases after cooling, the increase in strength is limited. Therefore, to further enhance the adhesion effect of the ceramic film, this invention adds a tempering process after water pressing, raising the tempering temperature to above 250℃. At this temperature, the acetal groups in PVB will undergo a cross-linking reaction, and the molecular chains will become entangled, thus improving the tensile strength of the ceramic film. However, the nickel in the internal electrode will oxidize above 260℃. Therefore, nitrogen gas is introduced throughout the tempering process to avoid nickel oxidation. This invention also adds a PET separator film between the blocks to prevent the ceramic films from sticking together after heat treatment, which would affect the normal cutting process in the subsequent station.

[0017] 3. In this invention, a concave screen is used for printing. By increasing the proportion of the blank ceramic film on the cutting end face, the inhibitory effect of the blank ceramic film on the separation between the electrode ceramic film layers can be enhanced. Compared with a flat screen, the electrode protrusion area on the cutting end face of the concave screen will be reduced by about 1 / 2. By reducing the protrusion area of ​​the electrode, the stress difference between the ceramic film and the electrode is reduced, thereby significantly reducing the cutting cracking rate. Attached Figure Description

[0018] Figure 1 This is a single-layer cross-sectional view of the high-capacity product obtained by using a concave screen printing plate in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the cut end face of the high-capacity product obtained by using a concave screen printing plate in Embodiment 1 of the present invention; Figure 3This is a single-layer cross-sectional schematic diagram of the high-capacity product prepared using a normal screen printing plate in Comparative Example 4 of the present invention; Figure 4 This is a schematic diagram of the cut end face of the high-capacity product obtained using a normal screen printing plate in Comparative Example 4 of the present invention; Figure 5 This is a photograph of the cut end face of the high-capacity product obtained under the process conditions of Example 1 of the present invention. Figure 6 This is a photograph of the cut end face of the high-capacity product obtained under the process conditions of Example 3 of the present invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] In the following specific implementation, The ceramic powder has a particle size D50 of 0.4~0.6μm, a dielectric constant of 35, and a BET (specific surface area) of 7~10m². 2 / g; The dispersant is polyacrylamide, model BIBO-PAM; The solvent is a mixture of ethanol and toluene in a mass ratio of 1:1; The plasticizer is diisononyl phthalate.

[0021] Example 1: A process method for improving the cutting cracking of large-size, high-capacity C0G products, specifically including the following steps: Step 1: Slurry preparation: Mix ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate evenly and stir at high speed to obtain a slurry; Step 2: Take a ceramic film and use a concave screen to print the first capacity electrode layer to obtain the first electrode ceramic film; take a ceramic film and use a concave screen to print the second capacity electrode layer to obtain the second electrode ceramic film... take a ceramic film and use a concave screen to print the capacity adjustment electrode layer to obtain the Nth electrode ceramic film; take N electrode ceramic films coated with slurry and stack them alternately in pairs to form a structure of "ceramic film-first electrode ceramic film-second electrode ceramic film...Nth electrode ceramic film-ceramic film" to obtain a laminated substrate; Step 3: Perform hydrostatic treatment on the laminated substrate, remove it after hydrostatic treatment, temper it under nitrogen atmosphere protection, and then cut it to obtain a large-size high-capacity C0G product; In Step 2, N=26 0; In step 1, the mass ratio of ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate is 10:0.3:2.5:3.0:0.3; In step 1, the molecular weight of high molecular weight PVB is 80,000; In step 1, the high-speed stirring process conditions are: rotation speed 1200 r / min, time 8 h; In step 2, the thickness of the ceramic film is 7 μm; In step 2, the printing thickness of the first capacity electrode layer, the second capacity electrode layer, and the capacity adjustment electrode layer is 1.5 μm; In step 2, the coating thickness of the slurry is 20 μm; In step 2, the water pressure treatment process conditions are: temperature 95℃, pressure 150 MPa, heating rate 1.5℃ / min, pressure rate 3 MPa / min; In step 2, the tempering treatment process conditions are: temperature 300℃, heating rate 3℃ / min, tempering time 3.0 h.

[0022] Example 2: Compared with Example 1, PVB with a molecular weight of 80,000 was replaced with PVB with a molecular weight of 60,000, while keeping other conditions unchanged. A process method for improving the cutting cracking of large-size, high-capacity COG products specifically includes the following steps: Step 1: Slurry preparation: Mix ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate evenly and stir at high speed to obtain a slurry; Step 2: Take a ceramic film and use a concave screen to print the first capacity electrode layer to obtain the first electrode ceramic film; take a ceramic film and use a concave screen to print the second capacity electrode layer to obtain the second electrode ceramic film... take a ceramic film and use a concave screen to print the capacity adjustment electrode layer to obtain the Nth electrode ceramic film; take N electrode ceramic films coated with slurry and stack them alternately in pairs to form a structure of "ceramic film-first electrode ceramic film-second electrode ceramic film...Nth electrode ceramic film-ceramic film" to obtain a laminated substrate; Step 3: Perform hydrostatic treatment on the laminated substrate, remove it after hydrostatic treatment, temper it under nitrogen atmosphere protection, and then cut it to obtain a large-size high-capacity C0G product; In Step 2, N=26 0; In step 1, the mass ratio of ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate is 10:0.3:2.5:3.0:0.3; In step 1, the molecular weight of high molecular weight PVB is 60,000; In step 1, the high-speed stirring process conditions are: rotation speed 1200 r / min, time 8 h; In step 2, the thickness of the ceramic film is 7 μm; In step 2, the printing thickness of the first capacity electrode layer, the second capacity electrode layer, and the capacity adjustment electrode layer is 1.5 μm; In step 2, the coating thickness of the slurry is 20 μm; In step 2, the water pressure treatment process conditions are: temperature 95℃, pressure 150 MPa, heating rate 1.5℃ / min, pressure rate 3 MPa / min; In step 2, the tempering treatment process conditions are: temperature 300℃, heating rate 3℃ / min, tempering time 3.0 h.

[0023] Example 3: Taking Example 1 as an example, the PVB with a molecular weight of 80,000 was replaced with PVB with a molecular weight of 40,000. All other conditions remained the same as in Example 1. The specific steps are as follows: Step 1: Slurry preparation: Mix ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate evenly and stir at high speed to obtain a slurry; Step 2: Take a ceramic film and use a concave screen to print the first capacity electrode layer to obtain the first electrode ceramic film; take a ceramic film and use a concave screen to print the second capacity electrode layer to obtain the second electrode ceramic film... take a ceramic film and use a concave screen to print the capacity adjustment electrode layer to obtain the Nth electrode ceramic film; take N electrode ceramic films coated with slurry and stack them alternately in pairs to form a structure of "ceramic film-first electrode ceramic film-second electrode ceramic film...Nth electrode ceramic film-ceramic film" to obtain a laminated substrate; Step 3: Perform hydrostatic treatment on the laminated substrate, remove it after hydrostatic treatment, temper it under nitrogen atmosphere protection, and then cut it to obtain a large-size high-capacity C0G product; In Step 2, N=26 0; In step 1, the mass ratio of ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate is 10:0.3:2.5:3.0:0.3; In step 1, the molecular weight of high molecular weight PVB is 40,000; In step 1, the high-speed stirring process conditions are: rotation speed 1200 r / min, time 8 h; In step 2, the thickness of the ceramic film is 7 μm; In step 2, the printing thickness of the first capacity electrode layer, the second capacity electrode layer, and the capacity adjustment electrode layer is 1.5 μm; In step 2, the coating thickness of the slurry is 20 μm; In step 2, the water pressure treatment process conditions are: temperature 95℃, pressure 150 MPa, heating rate 1.5℃ / min, pressure rate 3 MPa / min; In step 2, the tempering treatment process conditions are: temperature 300℃, heating rate 3℃ / min, tempering time 3.0 h.

[0024] Example 4: Taking Example 1 as an example, the concave screen is replaced with a normal screen, and all other conditions remain the same as in Example 1. The specific steps are as follows: Step 1: Slurry preparation: Mix ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate evenly and stir at high speed to obtain a slurry; Step 2: Take a ceramic film, use a normal screen printing plate to print the first capacity electrode layer to obtain the first electrode ceramic film; take a ceramic film, use a normal screen printing plate to print the second capacity electrode layer to obtain the second electrode ceramic film... take a ceramic film, use a normal screen printing plate to print the capacity adjustment electrode layer to obtain the Nth electrode ceramic film; take N electrode ceramic films coated with slurry and stack them alternately in pairs to form a structure of "ceramic film-first electrode ceramic film-second electrode ceramic film...Nth electrode ceramic film-ceramic film" to obtain a laminated substrate; Step 3: Perform hydrostatic treatment on the laminated substrate, remove it after hydrostatic treatment, temper it under nitrogen atmosphere protection, and then cut it to obtain a large-size high-capacity C0G product; In Step 2, N=26 0; In step 1, the mass ratio of ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate is 10:0.3:2.5:3.0:0.3; In step 1, the molecular weight of high molecular weight PVB is 80,000; In step 1, the high-speed stirring process conditions are: rotation speed 1200 r / min, time 8 h; In step 2, the thickness of the ceramic film is 7 μm; In step 2, the printing thickness of the first capacity electrode layer, the second capacity electrode layer, and the capacity adjustment electrode layer is 1.5 μm; In step 2, the coating thickness of the slurry is 20 μm; In step 2, the water pressure treatment process conditions are: temperature 95℃, pressure 150 MPa, heating rate 1.5℃ / min, pressure rate 3 MPa / min; In step 2, the tempering treatment process conditions are: temperature 300℃, heating rate 3℃ / min, tempering time 3.0 h.

[0025] Example 5: Taking Example 1 as an example, the tempering temperature was adjusted to 250℃, while the other conditions remained unchanged, the same as in Example 1, as follows: Step 1: Slurry preparation: Mix ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate evenly and stir at high speed to obtain a slurry; Step 2: Take a ceramic film and use a concave screen to print the first capacity electrode layer to obtain the first electrode ceramic film; take a ceramic film and use a concave screen to print the second capacity electrode layer to obtain the second electrode ceramic film... take a ceramic film and use a concave screen to print the capacity adjustment electrode layer to obtain the Nth electrode ceramic film; take N electrode ceramic films coated with slurry and stack them alternately in pairs to form a structure of "ceramic film-first electrode ceramic film-second electrode ceramic film...Nth electrode ceramic film-ceramic film" to obtain a laminated substrate; Step 3: Perform hydrostatic treatment on the laminated substrate, remove it after hydrostatic treatment, temper it under nitrogen atmosphere protection, and then cut it to obtain a large-size high-capacity C0G product; In Step 2, N=26 0; In step 1, the mass ratio of ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate is 10:0.3:2.5:3.0:0.3; In step 1, the molecular weight of high molecular weight PVB is 80,000; In step 1, the high-speed stirring process conditions are: rotation speed 1200 r / min, time 8 h; In step 2, the thickness of the ceramic film is 7 μm; In step 2, the printing thickness of the first capacity electrode layer, the second capacity electrode layer, and the capacity adjustment electrode layer is 1.5 μm; In step 2, the coating thickness of the slurry is 20 μm; In step 2, the water pressure treatment process conditions are: temperature 95℃, pressure 150 MPa, heating rate 1.5℃ / min, pressure rate 3 MPa / min; In step 2, the tempering treatment process conditions are: temperature 250℃, heating rate 3℃ / min, tempering time 3.0 h.

[0026] Example 6: Taking Example 1 as an example, the tempering time is shortened to 2.0 hours, while the other conditions remain unchanged, the same as in Example 1, as follows: Step 1: Slurry preparation: Mix ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate evenly and stir at high speed to obtain a slurry; Step 2: Take a ceramic film and use a concave screen to print the first capacity electrode layer to obtain the first electrode ceramic film; take a ceramic film and use a concave screen to print the second capacity electrode layer to obtain the second electrode ceramic film... take a ceramic film and use a concave screen to print the capacity adjustment electrode layer to obtain the Nth electrode ceramic film; take N electrode ceramic films coated with slurry and stack them alternately in pairs to form a structure of "ceramic film-first electrode ceramic film-second electrode ceramic film...Nth electrode ceramic film-ceramic film" to obtain a laminated substrate; Step 3: Perform hydrostatic treatment on the laminated substrate, remove it after hydrostatic treatment, temper it under nitrogen atmosphere protection, and then cut it to obtain a large-size high-capacity C0G product; In Step 2, N=26 0; In step 1, the mass ratio of ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate is 10:0.3:2.5:3.0:0.3; In step 1, the molecular weight of high molecular weight PVB is 80,000; In step 1, the high-speed stirring process conditions are: rotation speed 1200 r / min, time 8 h; In step 2, the thickness of the ceramic film is 7 μm; In step 2, the printing thickness of the first capacity electrode layer, the second capacity electrode layer, and the capacity adjustment electrode layer is 1.5 μm; In step 2, the coating thickness of the slurry is 20 μm; In step 2, the water pressure treatment process conditions are: temperature 95℃, pressure 150 MPa, heating rate 1.5℃ / min, pressure rate 3 MPa / min; In step 2, the tempering treatment process conditions are: temperature 300℃, heating rate 3℃ / min, tempering time 2.0 h.

[0027] Example 7: Taking Example 1 as an example, the tempering time is shortened to 1.0 h, while the other conditions remain unchanged, the same as in Example 1, as follows: Step 1: Slurry preparation: Mix ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate evenly and stir at high speed to obtain a slurry; Step 2: Take a ceramic film and use a concave screen to print the first capacity electrode layer to obtain the first electrode ceramic film; take a ceramic film and use a concave screen to print the second capacity electrode layer to obtain the second electrode ceramic film... take a ceramic film and use a concave screen to print the capacity adjustment electrode layer to obtain the Nth electrode ceramic film; take N electrode ceramic films coated with slurry and stack them alternately in pairs to form a structure of "ceramic film-first electrode ceramic film-second electrode ceramic film...Nth electrode ceramic film-ceramic film" to obtain a laminated substrate; Step 3: Perform hydrostatic treatment on the laminated substrate, remove it after hydrostatic treatment, temper it under nitrogen atmosphere protection, and then cut it to obtain a large-size high-capacity C0G product; In Step 2, N=26 0; In step 1, the mass ratio of ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate is 10:0.3:2.5:3.0:0.3; In step 1, the molecular weight of high molecular weight PVB is 80,000; In step 1, the high-speed stirring process conditions are: rotation speed 1200 r / min, time 8 h; In step 2, the thickness of the ceramic film is 7 μm; In step 2, the printing thickness of the first capacity electrode layer, the second capacity electrode layer, and the capacity adjustment electrode layer is 1.5 μm; In step 2, the coating thickness of the slurry is 20 μm; In step 2, the water pressure treatment process conditions are: temperature 95℃, pressure 150 MPa, heating rate 1.5℃ / min, pressure rate 3 MPa / min; In step 2, the tempering treatment process conditions are: temperature 300℃, heating rate 3℃ / min, tempering time 1.0 h.

[0028] Example 8: Taking Example 1 as an example, the tempering temperature was lowered to 250℃, the tempering time was shortened to 1.0 h, and the other conditions remained unchanged, the same as in Example 1, as follows: Step 1: Slurry preparation: Mix ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate evenly and stir at high speed to obtain a slurry; Step 2: Take a ceramic film and use a concave screen to print the first capacity electrode layer to obtain the first electrode ceramic film; take a ceramic film and use a concave screen to print the second capacity electrode layer to obtain the second electrode ceramic film... take a ceramic film and use a concave screen to print the capacity adjustment electrode layer to obtain the Nth electrode ceramic film; take N electrode ceramic films coated with slurry and stack them alternately in pairs to form a structure of "ceramic film-first electrode ceramic film-second electrode ceramic film...Nth electrode ceramic film-ceramic film" to obtain a laminated substrate; Step 3: Perform hydrostatic treatment on the laminated substrate, remove it after hydrostatic treatment, temper it under nitrogen atmosphere protection, and then cut it to obtain a large-size high-capacity C0G product; In Step 2, N=26 0; In step 1, the mass ratio of ceramic powder, polyacrylamide, solvent, high molecular weight PVB, and diisononyl phthalate is 10:0.3:2.5:3.0:0.3; In step 1, the molecular weight of high molecular weight PVB is 80,000; In step 1, the high-speed stirring process conditions are: rotation speed 1200 r / min, time 8 h; In step 2, the thickness of the ceramic film is 7 μm; In step 2, the printing thickness of the first capacity electrode layer, the second capacity electrode layer, and the capacity adjustment electrode layer is 1.5 μm; In step 2, the coating thickness of the slurry is 20 μm; In step 2, the water pressure treatment process conditions are: temperature 95℃, pressure 150 MPa, heating rate 1.5℃ / min, pressure rate 3 MPa / min; In step 2, the tempering treatment process conditions are: temperature 250℃, heating rate 3℃ / min, tempering time 1.0 h.

[0029] Example 9: Compared with Example 1, the ceramic film was replaced with a ceramic film with a thickness of 5.6 μm, the printing thickness of the capacity electrode layer was adjusted to 1.1 μm, and the other conditions remained the same as in Example 1.

[0030] Comparative Example 1: Taking Example 1 as an example, the tempering temperature was adjusted to 200°C, and the other conditions remained unchanged, the same as in Example 1.

[0031] Comparative Example 2: Compared with Example 1, the tempering temperature was reduced to 200°C, the tempering time was shortened to 1.0 h, the concave screen was replaced with a normal screen, and PVB with a molecular weight of 60,000 was selected as the binder. All other conditions remained the same as in Example 1.

[0032] Comparative Example 3: Compared with Example 1, the ceramic powder was replaced with a particle size D50 of 0.7 μm, a dielectric constant of 41, and a BET of 10 m. 2 / g of ceramic powder, with other conditions remaining unchanged, the same as in Example 1.

[0033] Comparative Example 4: Compared with Example 9, the ceramic film was replaced with a ceramic film with a thickness of 3.4 μm, the printing thickness of the capacity electrode layer was adjusted to 0.9 μm, N=300, and the other conditions remained the same as in Example 9.

[0034] Experiment: The large-size, high-capacity C0G-type products obtained in the examples and comparative examples were tested for their cutting crack rate;

[0035] Based on the data in the table above, the following conclusions can be drawn: Compared to Example 1, the increased product cutting cracking rate in Examples 2 and 3 is due to the decrease in molecular weight of PVB, leading to a decrease in the tensile strength of the ceramic film. In Example 4, replacing the concave screen with a normal screen resulted in an increased product cutting cracking rate, which is attributed to the blank ceramic film at the end losing its constraint on the electrode ceramic film, thus reducing its shear resistance. The increased product cutting cracking rate in Examples 5 to 8 is due to incomplete PVB crosslinking reaction as the tempering temperature and time decrease, resulting in a decrease in the shear resistance of the ceramic film. In Example 9 and Comparative Examples 3 and 4, the product cutting cracking rate remained at 0, indicating that this method has wide applicability to ceramic films of different powders and thicknesses, and possesses high stability. In summary, the selection of PVB molecular weight, the selection of screen type, and the setting of tempering process parameters in this invention help to reduce the product cutting crack ratio and reduce the occurrence of cracking.

[0036] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A process method for improving the cutting cracking of large-size, high-capacity COG-type products, characterized in that: Includes the following steps: Step 1: Slurry preparation: Take ceramic powder, dispersant, solvent, high molecular weight PVB and plasticizer, mix them evenly, and stir at high speed to obtain slurry; Step 2: Take a ceramic film, and use a concave screen to print the first capacity electrode layer to obtain the first electrode ceramic film; take a ceramic film, and use a concave screen to print the second capacity electrode layer to obtain the second electrode ceramic film... take a ceramic film, and use a concave screen to print the capacity adjustment electrode layer to obtain the Nth electrode ceramic film; take N Nth electrode ceramic films coated with paste and stack them alternately in pairs to form a structure of "ceramic film-first electrode ceramic film-second electrode ceramic film...Nth electrode ceramic film-ceramic film" to obtain a laminated substrate; Step 3: Perform hydrostatic treatment on the laminated substrate. After hydrostatic treatment, remove the substrate and perform tempering treatment under nitrogen atmosphere protection. Then cut the substrate to obtain a large-size high-capacity C0G type product. In step 2, 5 < N < 300.

2. The process method for improving the cutting cracking of large-size, high-capacity COG-type products according to claim 1, characterized in that: In step 1, the molecular weight of the high molecular weight PVB is 50,000 to 100,000.

3. The process method for improving the cutting cracking of large-size, high-capacity COG-type products according to claim 1, characterized in that: In step 1, the mass ratio of ceramic powder, dispersant, solvent, high molecular weight PVB, and plasticizer is 10: (0.1~0.3): (1.5~2.5): (2.0~3.0): (0.1~0.3).

4. The process method for improving the cutting cracking of large-size, high-capacity COG-type products according to claim 1, characterized in that: In step 1, the process conditions for high-speed stirring are: rotation speed 1000~1200 r / min, time 6~8 h.

5. The process method for improving the cutting cracking of large-size, high-capacity COG-type products according to claim 1, characterized in that: In step 1, the solvent is one or a mixture of ethanol, isopropanol, and toluene; In step 1, the plasticizer is one or a mixture of diisononyl phthalate, dioctyl phthalate, and diisodecyl phthalate; In step 1, the dispersant is polyacrylamide.

6. The process method for improving the cutting cracking of large-size, high-capacity COG-type products according to claim 1, characterized in that: In step 2, the printing thickness of the first capacity electrode layer, the second capacity electrode layer, and the capacity adjustment electrode layer is 0.5~2μm.

7. The process method for improving the cutting cracking of large-size, high-capacity COG-type products according to claim 1, characterized in that: In step 2, the thickness of the ceramic membrane is 5~10μm.

8. The process method for improving the cutting cracking of large-size, high-capacity COG-type products according to claim 1, characterized in that: In step 3, during the tempering process, a PET film is placed between each laminated substrate; The thickness of the PET film is 5~15μm.

9. The process method for improving the cutting cracking of large-size, high-capacity COG-type products according to claim 1, characterized in that: In step 2, the tempering process conditions are: temperature 250~300℃, heating rate 2~3℃ / min, and tempering time 1.0~3.0h.

10. The process method for improving the cutting cracking of large-size, high-capacity COG-type products according to claim 1, characterized in that: In step 2, the process conditions for water pressure treatment are: temperature 85~105℃, pressure 100~150MPa, heating rate 0.5~1.5℃ / min, and pressure rate 2~3MPa / min.

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