Ceramic binder, ceramic slurry and ceramic sheet

Abstract

The application provides a ceramic binder, which comprises a polymer containing a polar structural unit, a hard structural unit and a flexible structural unit; the flexible structural unit has a glass transition temperature Tg of 0 DEG C or below and a weight average molecular weight of 1000-4000; and the flexible structural unit contains a linear structure containing an oxygen element. The ceramic binder is used in a ceramic powder containing borate, and a ceramic sheet prepared by using the ceramic binder has high tensile strength and good flexibility.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of low temperature co-fired ceramics, and particularly relates to a ceramic binder, a ceramic slurry and a ceramic sheet. BACKGROUND

[0002] Low temperature co-fired ceramics (LTCC) as an important branch of modern electronic packaging field, due to its excellent electrical properties, mechanical strength, thermal stability and processability, plays an irreplaceable role in the construction of high frequency, high speed and high density electronic systems.

[0003] The manufacturing process of LTCC generally includes the following steps: firstly, the ceramic powder is subjected to ball milling and dispersion treatment, then a plasticizer and a binder are added, and the ball milling and mixing are continued, and after the defoaming treatment, a ceramic slurry composition with suitable viscosity is obtained. Then, using a doctor blade, an inverse roller coating machine and the like, a casting forming is carried out. After removing the volatile components such as solvents by heating and the like, the ceramic sheet is peeled off from the base film. The conductive paste for forming the internal electrode is coated on the obtained ceramic sheet by using a screen printing process, and the coated ceramic sheet is alternately overlapped in multiple layers, and is subjected to heating and pressure bonding to form a laminated body. Subsequently, the adhesive resin components and the like in the laminated body are subjected to thermal decomposition treatment (i.e. degreasing treatment) to remove these components. Thereafter, after a sintering process, a ceramic sintered body is obtained, and an external electrode is sintered on the end surface thereof, and finally a laminated ceramic capacitor is manufactured.

[0004] In the field of LTCC technology, the glass / ceramic composite system is the most widely used system at present, and among them, the borate glass system with B2O3-SiO2 as the main component is concerned because it can significantly reduce the sintering temperature. In the traditional preparation process, the binder is generally selected as polyvinyl butyral resin (PVB). However, the tensile strength and other key properties of the ceramic sheet prepared by using the existing PVB binder are insufficient. SUMMARY

[0005] In order to solve the problem of insufficient tensile strength and other key properties of the ceramic sheet prepared by using the existing ceramic binder, the application provides a ceramic binder, a ceramic slurry and a ceramic sheet.

[0006] The purpose of the application is achieved by the following technical scheme.

[0007] In a first aspect, the present application provides a ceramic binder, which comprises a polymer, the polymer containing a polar structure unit, a hard structure unit and a flexible structure unit; the flexible structure unit has a glass transition temperature Tg of 0℃ or lower and a weight average molecular weight of 1000-4000; and the flexible structure unit contains a linear chain structure containing oxygen elements.

[0008] Preferably, the linear chain structure containing oxygen elements in the flexible structure unit is a linear polyether structure.

[0009] Preferably, the flexible structure unit comprises a polyether-based acrylate structure unit, and / or the polyether-based acrylate structure unit has a glass transition temperature Tg of -10 to -90℃.

[0010] Preferably, the flexible structure unit is selected from one or more of a polyethylene glycol monomethyl ether acrylate structure unit, a polyethylene glycol monoethyl ether acrylate structure unit, a polyethylene glycol monomethyl ether methacrylate structure unit, a polyethylene glycol monoethyl ether methacrylate structure unit, and a polypropylene glycol monomethyl ether methacrylate structure unit.

[0011] Preferably, the hard structure unit has a glass transition temperature Tg1 of 80℃ or higher.

[0012] Preferably, the polar structure unit comprises any one or a combination of at least two of a hydroxyl group-containing structure unit, a carboxylic acid structure unit, an amide structure unit, and a sulfonic acid structure unit; and the hard structure unit comprises any one or a combination of at least two of an acrylate structure unit, an aromatic vinyl structure unit, and a nitrile structure unit.

[0013] Preferably, in the polymer, the mass ratio of the polar structure unit, the flexible structure unit and the hard structure unit is (1-5):(35-65):(35-65).

[0014] Preferably, the polymer has a glass transition temperature Tg2 of 0-30℃; and / or the polymer has a weight average molecular weight of 15w-30w.

[0015] In a second aspect, the present application provides a ceramic slurry, which comprises a ceramic powder and the ceramic binder as described above; the content of B2O3 in the ceramic powder is 20wt%-40wt%; and in the ceramic slurry, the content of the flexible structure unit of the ceramic binder is 15%-35% of the content of B2O3.

[0016] In a third aspect, the present application provides a ceramic sheet prepared from the ceramic slurry as described above.

[0017] Compared with the prior art, the present application has the following beneficial effects:

[0018] The present application provides a ceramic binder suitable for containing borate, the polymer contains polar structural units, hard structural units and flexible structural units; the glass transition temperature Tg of the flexible structural units is 0°C or lower, and the weight average molecular weight is 1000-4000; and, in the flexible structural units, a straight chain structure containing oxygen elements is contained. The present inventors found through a large number of research and analysis that when the ceramic binder is used in a ceramic slurry, and the content of B2O3 in the ceramic powder is 20wt%-40wt%; the content of the flexible structural units of the ceramic binder in the ceramic slurry is 15%-35% of the content of B2O3, the flexible structural units with specific structure in the above ceramic binder can have a good Lewis acid-base effect with B2O3 in the ceramic powder, improve the compatibility of the ceramic binder and the ceramic powder, and are beneficial to improving the tensile strength and elongation at break of the ceramic sheet. DETAILED DESCRIPTION

[0019] In order to make the technical problems, technical solutions and beneficial effects solved by the present application clearer, the present application will be further described in detail below in combination with specific embodiments. It should be understood that the embodiments described herein are part of the embodiments of the present application, rather than all the embodiments, and are used to explain the present application, but not to limit the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0020] In a first aspect, the present application provides a ceramic binder, the ceramic binder includes a polymer, the polymer contains polar structural units, hard structural units and flexible structural units; the glass transition temperature Tg of the flexible structural units is 0°C or lower, and the weight average molecular weight is 1000-4000; and, in the flexible structural units, a straight chain structure containing oxygen elements is contained.

[0021] In the present application, the glass transition temperature Tg of the flexible structural units is 0°C or lower, and the weight average molecular weight is 1000-4000; and, in the flexible structural units, a straight chain structure containing oxygen elements is contained. When the ceramic binder is used in a borate-based ceramic powder with a specific content of B2O3 (20wt%-40wt%), the content of the above flexible structural units is controlled to be 15%-35% of the content of B2O3, the flexible structural units with specific structure in the above ceramic binder can have a good Lewis acid-base effect with B2O3 in the ceramic powder, improve the compatibility of the ceramic binder and the ceramic powder, and are beneficial to improving the tensile strength and elongation at break of the ceramic sheet.

[0022] In the present application, the glass transition temperature Tg of the flexible structural unit is 0℃ or lower. More preferably, the glass transition temperature Tg of the flexible structural unit is -10~ -90℃, and further preferably -30~ -70℃.

[0023] Preferably, the linear structure of the oxygen-containing element in the flexible structural unit is a linear polyether structure. According to the present application, as a preferred case, the above flexible structural unit includes a polyether acrylate structural unit. Specifically, the flexible structural unit is preferably selected from one or more of a polyethylene glycol monomethyl ether acrylate structural unit, a polyethylene glycol monoethyl ether acrylate structural unit, a polyethylene glycol monomethyl ether methacrylate structural unit, a polyethylene glycol monoethyl ether methacrylate structural unit, and a polypropylene glycol monomethyl ether methacrylate structural unit.

[0024] To further improve the tensile strength and elongation at break of the ceramic sheet, the weight average molecular weight of the flexible structural unit is 1500~3500, and specifically, can be 1500, 2000, 2500, 3000, or 3500, etc. More preferably, it is 2000~3000.

[0025] According to the present application, as a preferred solution, the polymerization degree of the above flexible structural unit is 20~80. Specifically, it can be 20, 30, 40, 50, 60, 70, or 80, etc. More preferably, it is 40~60.

[0026] In the present application, preferably, the glass transition temperature Tg1 of the hard structural unit is 80℃ or higher, and more preferably 80~130℃. Specifically, the hard structural unit includes any one or a combination of at least two of an acrylate structural unit, an aromatic vinyl structural unit, and a nitrile structural unit.

[0027] In some specific embodiments, the hard structural unit includes any one or a combination of at least two of a methyl methacrylate structural unit, a tert-butyl methacrylate structural unit, an isobornyl methacrylate structural unit, a styrene structural unit, an α-methyl styrene structural unit, an acrylonitrile structural unit, and a methacrylonitrile structural unit.

[0028] In the present application, the polar structural unit includes any one or a combination of at least two of a hydroxyl-containing structural unit, a carboxylic acid structural unit, an amide structural unit, and a sulfonic acid structural unit. Preferably, it includes any one or a combination of at least two of an amide structural unit and a carboxylic acid structural unit.

[0029] Specifically, the polar structural unit includes any one of an acrylic acid-2-hydroxyethyl ester structural unit, an acrylic acid-2-hydroxypropyl ester structural unit, an acrylic acid structural unit, a methacrylic acid structural unit, an acrylamide structural unit, a methacrylamide structural unit, a 2-acrylamide-2-methylpropane sulfonic acid structural unit or a combination of at least two of them, and more preferably any one of or a combination of at least two of the acrylic acid structural unit, the methacrylic acid structural unit, the acrylamide structural unit, the methacrylamide structural unit and the 2-acrylamide-2-methylpropane sulfonic acid structural unit.

[0030] Preferably, in the polymer, the mass ratio of the polar structural unit, the flexible structural unit and the hard structural unit is (1-5):(35-65):(35-65).

[0031] Specifically, the mass ratio of the polar structural unit, the flexible structural unit and the hard structural unit can be 5:35:60, 5:40:55, 5:50:45, 5:60:35, 1:65:34, 2:55:43, 3:47:50 or 4:51:45, etc.

[0032] In the present application, the polar structural unit, the hard structural unit and the flexible structural unit are obtained by polymerization of polar monomers, hard monomers and soft monomers, respectively. Among them, the monomers exist in the form of corresponding structural units in the polymer obtained by polymerization. The glass transition temperature, mass ratio and molecular weight of each type of structural unit are based on the glass transition temperature, mass ratio and molecular weight of the corresponding monomers.

[0033] Each type of monomer can be obtained by commercial purchase. For example, for the aforementioned soft monomer, a monomer with corresponding parameters can be purchased according to the required molecular weight, number of linear carbon atoms, degree of polymerization and Tg.

[0034] In some specific embodiments, the glass transition temperature Tg2 of the polymer is 0-30℃.

[0035] Specifically, the glass transition temperature Tg2 of the polymer can be 0℃, 5℃, 10℃, 14℃, 18℃, 20℃, 25℃ or 30℃, etc.

[0036] In some specific embodiments, the weight average molecular weight of the polymer is 15w-30w.

[0037] Specifically, the weight average molecular weight of the polymer can be 15w, 20w, 22.5w, 26w, 28w or 30w, etc.

[0038] The polymer of the present application can be prepared by a conventional free radical polymerization method. For example, the preparation method thereof can be:

[0039] Mix the polar monomer, soft monomer and hard monomer according to the proportion, add the initiator and solvent, react at 60-70℃ for 3-5h, then add the initiator again after heating to 75-80℃, continue to react for 5-7h, and the polymer of the ceramic binder can be obtained. The initiator can be azobisisobutyronitrile, and the addition amount is 0.5-2% of the total mass of the monomers. The solvent can be ethyl acetate, and the addition amount is 1.5-2 times of the total mass of the monomers.

[0040] In some specific embodiments, the tensile strength of the prepared ceramic binder adhesive film is 20-40 MPa, and the elongation at break is 50%-100%.

[0041] In a second aspect, the present application provides a ceramic slurry comprising a ceramic powder and the ceramic binder as described above, wherein the content of B2O3 in the ceramic powder is 20wt%-40wt%, and the content of the flexible structural unit of the ceramic binder in the ceramic slurry is 15%-35% of the content of B2O3. At this time, it is very beneficial to further improve the tensile strength and elongation at break of the ceramic sheet.

[0042] Preparation method of the ceramic slurry of the present application:

[0043] a) primary ball milling of the ceramic powder, solvent and dispersant for 2-4h, the mass ratio of the raw materials (ceramic powder, solvent and dispersant) to the grinding body is 1-3:1; the content of B2O3 in the ceramic powder is 20wt%-40wt%; the solvent is ethyl acetate, and the addition amount is 75-85% of the mass of the ceramic powder; the dispersant is oleic acid, and the addition amount is 0.5-2% of the mass of the ceramic powder;

[0044] b) adding the ceramic binder prepared by the present application and the plasticizer, the addition amount of the ceramic binder (based on the amount of the polymer) is 10-20% of the mass of the ceramic powder, and the plasticizer can be dioctyl phthalate, and the addition amount is 2-4% of the mass of the ceramic powder, and secondary ball milling is carried out for 8-12h, and the ceramic slurry can be obtained.

[0045] In some specific embodiments, the solid content of the prepared ceramic slurry is 45%-60%, and the viscosity is 1000-8000cp.

[0046] In a third aspect, the present application provides a ceramic sheet comprising the ceramic slurry as described above. The ceramic slurry prepared by the present application is cast into a ceramic sheet on a full-automatic casting machine.

[0047] In some specific embodiments, the tensile strength of the prepared ceramic sheet is 6-15 MPa, and the elongation at break is 6%-10%.

[0048] The specific embodiments of the present application will be further explained by the following examples and comparative examples.

[0049] The reagents, materials and instruments used in the following description are conventional reagents, conventional materials and conventional instruments, which are commercially available, and the reagents involved can also be synthesized by conventional synthesis methods. The methods in the examples are conventional methods in the art, unless otherwise specified. The monomers meeting the present application can be commercially available.

[0050] The glass transition temperature can be detected by GB / T 19466.1-2004 differential scanning calorimeter (DSC). The molecular weight of the polymer can be determined by gel permeation chromatography (GPC).

[0051] Example 1:

[0052] 1) Preparation of ceramic binder:

[0053] In a reaction kettle, 5 parts of acrylic acid, 40 parts of polyethylene glycol monomethyl ether acrylate (Tg-65℃, weight average molecular weight 2000, degree of polymerization 40), 55 parts of methyl methacrylate (Tg1 105℃) were mixed, 0.5 parts of azobisisobutyronitrile was added, 200 parts of ethyl acetate was added, and the reaction was carried out at 70℃ for 4 h; the temperature was raised to 75℃, and 0.5 parts of azobisisobutyronitrile was added, and the reaction was continued for 6 h to obtain a ceramic binder containing polymer. Among them, the glass transition temperature of the polymer is 15℃, and the weight average molecular weight is 15.8 w.

[0054] 2) Preparation of ceramic slurry

[0055] a) In a ball mill tank, the ceramic powder, solvent and dispersant were first ball milled for 3 h, and the mass ratio of raw materials (ceramic powder, solvent and dispersant) to grinding body was 2:1; the mass ratio of B2O3:SiO2:Al2O3 in the ceramic powder was 3:4:3, and the content of B2O3 in the ceramic powder was 30wt%; the solvent was ethyl acetate, and the amount of addition was 85% of the mass of the ceramic powder; the dispersant was oleic acid, and the amount of addition was 1% of the mass of the ceramic powder;

[0056] b) The ceramic binder and plasticizer prepared by the present application were added to the ball mill tank, the amount of addition of the ceramic binder (calculated by the amount of polymer) was 15% of the mass of the ceramic powder, and the plasticizer was dioctyl phthalate, the amount of addition was 3% of the mass of the ceramic powder, and the second ball milling was carried out for 10 h to obtain the ceramic slurry. The flexible structural unit in the ceramic binder is 20% of the mass of B2O3 in the ceramic slurry; the solid content of the ceramic slurry is 58.3%, the initial slurry viscosity is 1213cp, and the viscosity after standing for 24 h is 1219cp.

[0057] 3) Preparation of ceramic sheet:

[0058] The ceramic slurry prepared according to the present application was cast on a full-automatic casting machine to obtain a ceramic sheet with a thickness of 50 μm.

[0059] Example 2:

[0060] The ceramic binder, ceramic slurry and ceramic sheet were prepared according to the method of Example 1, and the main difference between Example 2 and Example 1 is that in the preparation of the ceramic binder, 5 parts of methacrylic acid, 40 parts of polyethylene glycol monomethyl ether acrylate (Tg of -63°C, weight average molecular weight of 1500, degree of polymerization of 30), 55 parts of tert-butyl methacrylate (Tg1 of 104°C) were selected; the glass transition temperature of the ceramic binder is 18°C, and the weight average molecular weight is 16.8w.

[0061] The remaining operation steps are the same.

[0062] Example 3:

[0063] The ceramic binder, ceramic slurry and ceramic sheet were prepared according to the method of Example 1, and the main difference between Example 3 and Example 1 is that in the preparation of the ceramic binder, 5 parts of acrylamide, 40 parts of polyethylene glycol monomethyl ether acrylate (Tg of -68°C, weight average molecular weight of 4000, degree of polymerization of 80), 55 parts of isobornyl methacrylate (Tg1 of 110°C) were selected; the glass transition temperature of the ceramic binder is 20°C, and the weight average molecular weight is 24.3w.

[0064] The remaining operation steps are the same.

[0065] Example 4:

[0066] The ceramic binder, ceramic slurry and ceramic sheet were prepared according to the method of Example 1, and the main difference between Example 4 and Example 1 is that in the preparation of the ceramic binder, 2 parts of methacrylamide, 50 parts of polypropylene glycol monomethyl ether methacrylate (Tg of -66°C, weight average molecular weight of 3000, degree of polymerization of 60), 48 parts of isobornyl methacrylate (Tg1 of 110°C) were selected; the glass transition temperature of the ceramic binder is -4°C, and the weight average molecular weight is 26.8w.

[0067] The remaining operation steps are the same.

[0068] Example 5:

[0069] The ceramic binder, ceramic slurry and ceramic sheet were prepared according to the method of Example 1, the main difference between Example 5 and Example 1 being that in the preparation of the ceramic binder, 4 parts of acrylamide, 50 parts of polyethylene glycol monoethyl ether acrylate (Tg of -62℃, molecular weight of 1000, degree of polymerization of 20), 26 parts of styrene (Tg1 of 100℃) and 20 parts of acrylonitrile (Tg1' of 125℃) were selected; the glass transition temperature of the ceramic binder was 0℃, and the molecular weight was 28.4w.

[0070] The remaining operation steps were the same.

[0071] Example 6:

[0072] The ceramic binder, ceramic slurry and ceramic sheet were prepared according to the method of Example 1, the main difference between Example 6 and Example 1 being that in the preparation of the ceramic slurry, the ceramic binder (based on the amount of polymer) was 20% of the mass of the ceramic powder, the mass ratio of B2O3:SiO2:Al2O3 in the ceramic powder was 2.5:4.5:3, and the content of B2O3 in the ceramic powder was 25wt%; the flexible structural unit in the ceramic binder was 32% of the mass of B2O3 in the ceramic slurry; the solid content of the ceramic slurry was 60%.

[0073] The remaining operation steps were the same.

[0074] Example 7:

[0075] The ceramic binder, ceramic slurry and ceramic sheet were prepared according to the method of Example 1, the main difference between Example 7 and Example 1 being that in the preparation of the ceramic slurry, the ceramic binder (based on the amount of polymer) was 8% of the mass of the ceramic powder, the mass ratio of B2O3:SiO2:Al2O3 in the ceramic powder was 2:4.5:3.5, and the content of B2O3 in the ceramic powder was 20wt%; the flexible structural unit in the ceramic binder was 16% of the mass of B2O3 in the ceramic slurry; the solid content of the ceramic slurry was 45%.

[0076] The remaining operation steps were the same.

[0077] Example 8:

[0078] The ceramic binder, ceramic slurry and ceramic sheet were prepared according to the method of Example 1, the main difference between Example 8 and Example 1 being that acrylic acid was replaced by 2-hydroxyethyl acrylate.

[0079] The remaining operation steps were the same.

[0080] Comparative Example 1:

[0081] Comparative Example 1 and Example 1 differ in that PVB resin was used as the ceramic binder.

[0082] The remaining operation steps are the same.

[0083] Comparative Example 2:

[0084] Comparative Example 2 differs from Example 1 in that it does not contain polyethylene glycol monomethyl ether acrylate.

[0085] The remaining operation steps are the same.

[0086] Comparative Example 3:

[0087] Comparative Example 3 differs from Example 1 in that the weight average molecular weight of the polyethylene glycol monomethyl ether acrylate is 500, and the glass transition temperature Tg is -61℃.

[0088] The remaining operation steps are the same.

[0089] Comparative Example 4:

[0090] Comparative Example 4 differs from Example 1 in that the weight average molecular weight of the polyethylene glycol monomethyl ether acrylate is 6000, and the glass transition temperature Tg is -70℃.

[0091] The remaining operation steps are the same.

[0092] Comparative Example 5:

[0093] Comparative Example 5 differs from Example 1 in that the polyethylene glycol monomethyl ether acrylate in Example 1 is replaced with isooctyl acrylate having a glass transition temperature Tg of -70℃.

[0094] The remaining operation steps are the same.

[0095] Comparative Example 6:

[0096] Comparative Example 6 differs from Example 1 in that in the preparation of the ceramic slurry, the ceramic binder (based on the amount of polymer) is 7.5% of the mass of the ceramic powder, the mass ratio of B2O3:SiO2:Al2O3 in the ceramic powder is 3:4:3, the content of B2O3 in the ceramic powder is 30wt%, and the flexible structural unit in the ceramic binder is 10% of the mass of B2O3 in the ceramic slurry.

[0097] The remaining operation steps are the same.

[0098] Comparative Example 7:

[0099] Comparative Example 7 differs from Example 1 in that in the preparation of the ceramic slurry, the ceramic binder (based on the amount of polymer) is 25% of the mass of the ceramic powder, the mass ratio of B2O3:SiO2:Al2O3 in the ceramic powder is 2:4.5:3.5, the content of B2O3 in the ceramic powder is 20wt%, and the flexible structural unit in the ceramic binder is 50% of the mass of B2O3 in the ceramic slurry.

[0100] The remaining operation steps are the same.

[0101] Performance test:

[0102] The ceramic binder, ceramic slurry and ceramic sheet prepared in the above examples and comparative examples were subjected to performance test.

[0103]

Tensile strength

[0104]

Elongation at break

[0105] The performance test results are shown in Table 1.

[0106] Table 1:

[0107]

[0108] From the test results of Examples 1-3, 5 and Example 4, it can be seen that when the glass transition temperature of the polymer is 0℃ or higher, the tensile strength of the ceramic sheet is stronger.

[0109] From the test results of Examples 1-3, 6 and Example 7, it can be seen that when the addition amount of the ceramic binder is 10-20% of the mass of the ceramic powder, the tensile strength of the ceramic sheet is stronger.

[0110] From the test results of Examples 1-8 and Comparative Example 1, it can be seen that compared with the traditional PVB resin, the tensile strength of the adhesive film of the ceramic binder of the application is stronger, and after the ceramic binder is configured into a slurry with the ceramic powder of the foregoing composition and prepared into a ceramic sheet, the tensile strength and flexibility of the ceramic sheet are significantly improved.

[0111] From the test results of Examples 1-8 and Comparative Example 2, it can be seen that compared with the binder without flexible structural units, the tensile strength of the adhesive film of the ceramic binder of the application is stronger and the flexibility is better; the tensile strength and flexibility of the ceramic sheet prepared by the application are significantly improved.

[0112] From the test results of Examples 1-8 and Comparative Examples 3-4, it can be seen that when the molecular weight of the flexible structural unit is too low or too high, the tensile strength or elongation at break of the ceramic sheet will decrease.

[0113] From the test results of Examples 1-8 and Comparative Example 5, it can be seen that when the flexible structural unit does not include an oxygen-containing linear structure, the tensile strength and elongation at break of the ceramic sheet will significantly decrease.

[0114] From the test results of Examples 1 to 8 and Comparative Examples 6 to 7, it can be seen that when the content of the flexible structural unit of the ceramic binder is too low or too high relative to the content of B2O3 in the ceramic powder, the tensile strength or elongation at break of the ceramic sheet decreases.

[0115] The application is further described in detail by the specific examples, but it should be understood that the specific description herein should not be construed as limiting the spirit and scope of the application, and various modifications made by those skilled in the art after reading the description above are within the scope of the application.

Claims

1. A ceramic slurry, characterized by, The ceramic slurry comprises a ceramic powder and a ceramic binder; The content of B2O3 in the ceramic powder is 20wt%-40wt%; The ceramic binder comprises a polymer, the polymer contains a polar structure unit, a hard structure unit and a flexible structure unit; the flexible structure unit has a glass transition temperature Tg of 0°C or lower and a weight average molecular weight of 1000-4000; and the flexible structure unit contains a linear chain structure containing an oxygen element; The hard structure unit has a glass transition temperature Tg1 of 80°C or higher; The hard structure unit comprises any one or a combination of at least two of a methyl methacrylate structure unit, a tert-butyl methacrylate structure unit, an isobornyl methacrylate structure unit, a styrene structure unit, an α-methyl styrene structure unit, an acrylonitrile structure unit and a methacrylonitrile structure unit; The polar structure unit comprises any one or a combination of at least two of a 2-hydroxyethyl acrylate structure unit, a 2-hydroxypropyl acrylate structure unit, an acrylic acid structure unit, a methacrylic acid structure unit, an acrylamide structure unit, a methacrylamide structure unit and a 2-acrylamide-2-methylpropane sulfonic acid structure unit; In the ceramic slurry, the content of the flexible structure unit of the ceramic binder is 15%-35% of the content of B2O3.

2. The ceramic slurry of claim 1, wherein, The linear chain structure containing an oxygen element in the flexible structure unit is a linear chain polyether structure.

3. The ceramic slurry of claim 1, wherein, The flexible structure unit comprises a polyether-based acrylate structure unit.

4. The ceramic slurry of claim 3, wherein, The polyether-based acrylate structure unit has a glass transition temperature Tg of -10°C to -90°C.

5. The ceramic slurry of any one of claims 1-4, wherein the ceramic slurry has a pH of about 6.5 to about 8.

5. The flexible structure unit is selected from one or more of a polyethylene glycol monomethyl ether acrylate structure unit, a polyethylene glycol monoethyl ether acrylate structure unit, a polyethylene glycol monomethyl ether methacrylate structure unit, a polyethylene glycol monoethyl ether methacrylate structure unit and a polypropylene glycol monomethyl ether methacrylate structure unit.

6. The ceramic slurry of claim 1, wherein, In the polymer, the mass ratio of the polar structure unit, the flexible structure unit and the hard structure unit is (1-5):(35-65):(35-65).

7. The ceramic slurry of claim 1, wherein, The polymer has a glass transition temperature Tg2 of 0°C-30°C.

8. The ceramic slurry of claim 1, wherein, The polymer has a weight average molecular weight of 15w-30w.

9. A ceramic sheet, characterized by, The ceramic slurry is prepared by any one of claims 1-8.

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